Food Report Final Document

Knowledge Transfer Network

UK Sensing technologies for contamination in food

Knowle Transfe Networ

CONTENTS

TABLE OF CONTENTS

3

Overview introduction Food and drink contamination Contaminated Products Types of physical contamination HACCP Recent High Profile Incidents Report objectives Primary Objective Secondary Objective Challenges Methodology Current Detection Approaches Current approaches Electromagnetic spectrum On-line Techniques X-ray imaging X-ray spectroscopy Raman spectroscopy Visual Inspection Infrared techniques Hyperspectral imaging Optical sorting Terahertz imaging Microwave detection Ultrasound Magnetic Separation Metal detection Sampling Electrical impedance Off-line / Lab-based Techniques Biosensors Nuclear magnetic resonance Microscopy Mass spectrometry Chromatography Polymerase Chain Reaction Enzyme-linked immunisorbent assay ATP Bioluminescence Technology Summary Table Challenges 1. The detection of glass fragments – in particulate food Background

7 8 8 11 12 15 15 16 16 16 17 18 19 20 20 21 21 23 25 27 28 31 33 35 37 39 41 42 43 44 46 46 47 49 51 52 53 54 55 56 57 58 58

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UK SENSING TECHNOLOGIES FOR CONTAMINATION IN FOOD

Current situation Manufacturers perspective Contaminant Characteristics Potential for innovation 2. The detection of glass fragments – liquids in glass Background Current situation Manufacturers perspective Contaminant Characteristics Potential for innovation 3. The detection of plastic Background Current situation Manufacturers perspective Contaminant Characteristics Potential for innovation 4. The detection and sensing of fat and gristle Background Current situation Manufacturers perspective Contaminant Characteristics Potential for innovation 5. The detection of bone in meat and poultry products and in fish Background Current situation Manufacturers perspective Contaminant Characteristics Potential for innovation 6. The detection of insects in fruits and vegetables Background Current situation Manufacturers perspective Contaminant Characteristics Potential for innovation 7. The quantification of ripeness in fruit Background Manufacturers perspective Contaminant Characteristics Potential for innovation 8. The detection of damage and mould in fruits and vegetables Background

58 58 59 59 60 60 60 60 61 61 62 62 62 62 63 63 64 64 64 64 64 65 67 67 67 67 68 68 69 69 69 69 70 70 72 72 72 73 73 75 75

CONTENTS

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Current situation Manufacturers perspective Contaminant Characteristics Potential for innovation 9. The identification of the wrong product in a package Background Current situation Manufacturers perspective Potential for innovation 10. The detection of “natural plant materials” Background Current situation Manufacturers perspective Contaminant Characteristics Potential for innovation 11. Hair and fibre contamination Background Current situation Contaminant Characteristics Potential for innovation 12. The detection of metal of any sort of food product Background Current situation Contaminant Characteristics Potential for innovation Conclusions Non-commercial / emergent technologies: Ready in linked sectors Barriers to innovation Appendix 1. UK capabilities in highlighted areas Guide to the Research Councils Terahertz Hyperspectral Capacitance and electrical impedance tomography Biosensors Ultrasonic Infra-red Techniques Raman Appendix 2: Inputs into the February Workshop Appendix 3: Acronyms About The Knowledge Transfer Network

75 75 76 76 78 78 78 79 79 80 80 80 80 81 81 82 82 82 82 82 83 83 83 83 84 85 85 85 86 87 90 91 94 97 97 100 103 106 109 112 114 116

The Knowledge Transfer Network: Food Sensing Report

OTHER

19%

STONE

RUBBER

3%

1%

GLASS

9%

ANIMAL

FOREIGN OBJECTS IN FOOD (2012)

METAL

32%

3%

PLASTIC

8%

AIOLN INC AT

THE

TH

WOOD

3%

E OEFD AUS T C O T S S REP R

AIOLN INC S T A Y PH AMI

HE T S I

CON

421

T

H T 7

FOOD INCIDENTS REPORTED TO THE FSA

E OEFD AUS C RT O T GES S REP

A E FS H T TO

LACRIDENT IN

1604

or ct se ch ea in th wi l Activity levewith relevance compared or to that sect

HIGH MEDI LOW UM

2012 2000

THE

21%

FSA

ACTIVITY RELEVANCE

T

PESTS

TERAHERTZ ULTRASONIC HYPERSPECTRAL INFRARED RAMAN TECHNIQUES

CAPACITANCE/ IMPEDANCE TOMOGRAPHY

BIOSENSORS

OVERVIEW

Overview

7

The Food Standards Agency (FSA) publishes data which shows a worrying – and increasing - amount of complaints due to contamination in food and drink. Complaints have risen year on year driven by numerous factors such as more mechanized process chain, higher consumer awareness, and more readily available and thorough testing equipment.  Physical contamination of food and drink from well-established food industry materials such as metal , plastic and glass still manage to evade the carefully constructed safety mechanisms established to trap them - frustrating manufacturers. Reported Incidents of contamination cause recalls of a product, costing money and severely harm food companies reputation - devastating to an industry who rely on consumer confidence. This problem is complicated given the varied and ever-increasing variety of materials, which are able to find their way into the food production chain.  The industry needs to be aware of what innovative sensing technologies are being developed not only in the food sector but in other sectors also. There are however inhibiting factors to innovation in this sector; food industry representatives are often looking for better versions of what already exists. Engagement events are key to exposing the up and coming technologies to food industry representatives to technology areas outside of their own areas of expertise and sector. Although a huge industry, the food industry can be very conservative in the adoption of new technologies and it can require much higher rates of return on capital investment than can be delivered, therefore the food industry seeks low- cost solutions that can justify the effort. The idea that product recalls can be reduced or prevented by better training, procedures etc. is a far more appealing alternative to large R&D investments. There is however, a plethora of new technologies whose sensitivity, specificity, cost and overall performance are beginning to align with the needs of the food industry. Optical methods can provide real-time imaging across many wavelengths to not only detect, buy characterise food properties as it passes through a factory. Techniques that can penetrate objects and visualise inside packages with abilities beyond what is achievable with X-rays only are being developed for Earth observation and military purposes which could find an unexpected application. Valuable insight to this report was provided by interaction with food companies through an online questionnaire, direct discussions and an interactive workshop help on the 25th February 2014 in London which bought together food industry experts, membership organisations and technologists in technologies identified as potentially useful by the Knowledge Transfer Network prior to the workshop.

The Knowledge Transfer Network: Food Sensing Report

UK SENSING TECHNOLOGIES FOR CONTAMINATION IN FOOD

introduction

Food and drink contamination Foreign body contamination in food is one of the major sources of complaints against food manufacturers [1]. ‘Incidents’ are hugely damaging for manufacturers as they can lead to injury, loss of brand loyalty and large recall expenses. Many public incidents such as glass contamination, E-coli, horsemeat in products labelled beef have shaken trust in the industry and made the public aware of how vulnerable parts of the food chain are to both intentional and non-intentional adulteration. Figure 1 shows the number of ‘incidents’ in food from 2000 in the UK, the increase should cause alarm for all involved (Refs. 2,3,4). The trend of increase was stalled slightly from 2006 – 2009, the subsequent increase could be due to a few factors; Since 2009 the number of pesticide residue ingredients has increased substantially. In 2011 and 2012, this was due partly to increased testing of okra at border inspection posts

1714 1505 1604 1344

1298 1312 1208

966

743 530

789

476 421

2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012

8

Figure 1. Number of food incidents, 2006 - 2012 adapted from Ref. 3

1. Edwards, M. (2004) Detecting foreign bodies in food, Cambridge: Woodhead Publishing Limited. 2. http://food.gov.uk/multimedia/pdfs/incidentsar.pdf Food Standards Agency (2007) 3. http://food.gov.uk/multimedia/pdfs/incidents-report-2012.pdf Food Standards Agency (2013) 4. It is important to appreciate that these figures are and are expected to be largely underestimated, by as much as a factor of 200 suggested by some at the Workshop. This misrepresentation could be die to a variety of reasons: • The severity of some of the incidences will bias figures towards those, for example, people will be more likely to report a piece of glass than a fish bone. • Once a problem is identified, mass withdrawals can hide the extent of the actual problem • Failure to report to the FSA Despite these obvious failings of the acquired data, the data is expected to be representative of industries problems.

INTRODUCTION

9

Incidents involving strains of salmonella has averaged out at 45 a year during 2006 – 2009. In 2010 they rose steeply to 118 and fell only to 98 in 2012. Our investigations suggest that this increase was mostly the result of paan leaves imported from Bangladesh (Ref. 3) The food and drink incidents are broken down into incident type in Figure 2 for years 2006 and 2012.

Allergens Animal feed (on market) Biocides Counterfeit product Environmental contamination Food contact materials Illegal import / export Irradiated ingredient Labelling / documentation

2006 2012

Microbiological contamination Natural chemical contamination On-farm Pesticides Physical contamination Process contamination Radiological TSE Use of an unauthorised ingredient Veterinary medicines Water quality

50

100

150

200

250

300

350

400

Figure 2. Incident by category 2006 and 2012, Ref.3

Physical contamination is one of the key subject areas of this report and in 2012 represented 7 % (the seventh largest category) of the total number of complaints. In Figure 3, specifically the incidents relating to physical contamination incidents The “number of incidents falling into this category increased from 93 in 2011 to 107 in 2012. In particular, incidents relating to metal contamination increased from 19 incidents in 2011 to 34 in 2012”, Ref. 3

The Knowledge Transfer Network: Food Sensing Report

UK SENSING TECHNOLOGIES FOR CONTAMINATION IN FOOD

Overall the physical contamination incidents have not been improved by a statistically significant amount over the past 6 years but for a slight dip in 2009.

139 123 116

110

107 93

2012

2011

2010

2009

2008

2007

56

2006

10

Figure 3. Incident of ‘Physical contamination’ 2006 - 2012, adapted from Ref. 3

INTRODUCTION

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Contaminated Products In Figure 4, the breakdown of all incidents in 2012 is shown by the food type they occur in. The highest categories of contamination are fruit and vegetables, meat and meat products and nuts and seeds. The range of detection schemes needed by the food industry is compounded by this large number of food mediums available. Fruit and vegetables Meat and meat products Nut, nut products and seeds Prepared foods and snacks Cereals and bakery products Molluscs Confectionary, honey and royal jelly Dietic foods and food supplements Fish and fish products Milk and milk products Herbs and spices Soups, broths and sauces Animal feeds Non-alcoholic beverages Poultry and poultry meat products Crustaceans Alcoholic beverages (other than wine) Cocao preparations, coffee and tea Fats and oils Eggs and egg products Water Wine Other foods Incidents not related to a specific food

50

100

150

200

250

300

Figure 4. Incidents by food type 2012

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UK SENSING TECHNOLOGIES FOR CONTAMINATION IN FOOD

Types of physical contamination The types of physical contamination present in food vary largely depending on the type of food in question, below is a short list of various contaminant types of concern: • Wood • Plastic • Metal • Glass • Animal origin • Paper and cardboard • and many more Figure 5 and Figure 6 show the types of foreign object complaints in 2006 to 2012 (from Refs. 2 and 3). Whilst the total number of foreign objects incidents each year has fallen from 139 to 107 in this time period, the proportion of metal incidents has risen and high-risk incidents such as plastics and glass remain high. The reason for this may be due to a more automated and mechanised supply chain. Metal

Metal

19%

Pests

19% 19%

Pests

19%

2% 3%

2% 3% 8%

24%

Glass

Glass

Animal Origin

8%

24%

Plastic Plastic

Animal Wood

13%

Origin

12%

Rubber

13%

Wood

12%

Other

Rubber Figure 5. Breakdown of the complaints made about foreign objects by object type (2006) Other Metal Metal

19% 32%

Pests Pests

19%

32%

1% 3%

1% 3% 3%

21%

9%

8% 21%

9%

Plastic Glass

3%

3% 3%

Plastic

8%

Animal GlassOrigin Wood

Animal Origin

Stone

Wood Rubber Other

Stone

Figure 6. Breakdown of the complaints made about foreign objects by object type (2012) Rubber

Other

The process stages in the production of a complex food are shown in Table 1 - shown also are common points of entry for common food contamination issues. The production stages are taken from Ref. 1 Table 1. Common points of entry for contamination challenges

PRODUCTION STAGE

CONTAMINANT

PRIME PRODUCER

Insects can enter the chain at any subsequent point in this chain, perhaps explaining why they are the second biggest complaint for food ‘incidents’, (Figure 6). Insect and pest contamination at this stage of the supply chain can occur as producers are under pressure to minimize pesticide applications. The use of biological pest control may mean that damaging insects are absent and the crop is in good visual condition, however the predator insects may be on the produce and brought into the food supply chain. Glass as the fourth largest concern can enter at this stage and through out as contaminants in the ground or later contamination by broken lights etc. although the later contamination risk is mitigated by the prevalence of factory safe light fittings. The fat and gristle content of meat varies hugely from animal to animal and is determined at this stage in the chain. Incorrect labeling can occur at any point throughout the entire food chain, making traceability and due diligence a key aspect of food manufacture.

HARVESTING

The harvesting process can pick up bad produce as well as physical contaminants that are present in the environment; screening is usually base heavily on visual inspection at this point. Whilst plastics can enter throughout the chain, major sources are often at the industrial processing stages, conveyer parts and tools for example. Again, for metal, mechanised processes often increase the likelihood of contamination at the processing stages, nuts, bolts etc. The fat and gristle content of meat are controlled at this butchery production stage. Fruit and vegetables are harvested at their ripest and checked for damage often by visual inspection after having been harvested indiscriminately. Depending on their level of ripeness mold contamination can occur at any stage subsequently.

TRANSPORTATION RAW MATERIAL PROCESSING (MILLING, ABATTOIR)

COLLATION / TRANSPORTATION

Bone can remain in meat and poultry products after incomplete filleting and de-boning. Extraneous vegetable matter (EVM) can remain during the milling process due to its similar composition to the parent foodstuff.

FOOD MANUFACTURER

Contamination at this stage can be due to many causes, five contamination channels at this stage could be: Contaminated raw ingredients from the stages above. Manufacturing machinery- rubber seals, metal swarf, nuts etc. Packaging that is used for the ingredient or processing steps, for example blue sacks. Factory environment – bristles from cleaning brushes Operators – objects that are introduced by the operators of the machinery, hair, plasters, jewelry etc

FOOD PROCESSING & ASSEMBLY COLLATION, TERTIARY PACKAGING, STORAGE DISTRIBUTION RETAILER RDC OR WHOLESALER / CATERER / STORAGE RETAIL DISPLAY

Contaminants beyond this stage are now out of the manufacturers ability to monitor.

CONSUMER PURCHASE & TRANSPORTATION

The consumer assesses ripeness in fresh fruit and vegetables at this stage.

HOME STORAGE FOOD PREPARATION PRESENTATION AND CONSUMPTION

INTRODUCTION

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HACCP Obviously, for foreign object contamination, prevention is better than cure and systems such as the Hazard Analysis and Critical Control Point (HACCP) exist which set out procedures for maintaining safe to eat food. Hazard Analysis and Critical Control Point (HACCP) is a system that helps food business operators look at how they handle food and introduces procedures to make sure the food produced is safe to eat. Ref. 5. As part of routine inspections, the enforcement officer will check that the business has an appropriate HACCP-based food safety management system in place. However, when these preventative steps fail, procedures and tests must be in place to detect these objects, ideally identify them and ideally locate the source of the contamination. Workshop delegates have additionally provided thought on the usefulness of sensors to not only directly detect contamination events, but also in the behavior i.e. the breaches of HACCP which can inevitably lead to incidences.

Recent High Profile Incidents Table 2. Recent high profile incidents 6,7,8,9,10,11,12,13,14

INCIDENT

REF

Cigarette in Mushrooms

2014

[6]

Wasp in Chocolate

2014

[7]

Toenail in Pasta Sauce

2012

[8]

Cocaine in Soft Drink

2013

[9]

Horsemeat scandal

2013

[10]

Caterpillar in Sweetcorn

2014

[11]

Peanut in Stuffing

2014

[12]

Metal in Pudding

2014

[13]

Allegens in Hot Dogs

2014

[14]

5. http://www.food.gov.uk/business-industry/caterers/haccp/ 6. http://www.dailymail.co.uk/news/article-2549331/Father-buys-pack-mushrooms-Co-op-store-finds-cigarettehidden-inside-given-just-92p-refund.html 7. http://uk.news.yahoo.com/wasp-found-inside-cadbury-dairy-milk-jake-keating-142659377.html#nHMfprI 8. http://uk.news.yahoo.com/aldi-customer-tracy-arnold-from-wisbech-shocked-after-finding-nail-in-pasta-sauce. html#mFVJ3Ri 9. http://www.food.gov.uk/news-updates/news/2013/dec/caribbean-soft-drink#.UvUan17t0_V 10. http://www.telegraph.co.uk/foodanddrink/foodanddrinknews/9859946/Horse-meat-scandal-More-contaminatedfood-likely-to-be-found.html 11. http://www.dailymail.co.uk/news/article-2553800/Mother-finds-INCH-long-caterpillar-inside-tin-sweetcornbought-Aldi.html 12. http://www.food.gov.uk/news-updates/allergy-news/2014/feb/sainsburys-stuffing#.U1pwXl6ppuY 13. http://www.food.gov.uk/news-updates/recalls-news/2014/feb/metal#.U1pwql6ppuY 14. http://www.bbc.co.uk/news/business-27100284

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UK SENSING TECHNOLOGIES FOR CONTAMINATION IN FOOD

Report objectives

This document aims to cover current detection systems used for a number of food and drink related complaints with input from food manufacturers current technologies will be assessed for their strengths and weaknesses. Through communication with manufacturers, technologist and consultancies future technologies are also highlighted. The UKTI have identified key challenge areas to be met in the field of contaminant sensing in food production. During the consultation period further challenges (in purple) have been identified and added in addition to the initial 10. This report has been compiled by the Knowledge Transfer Network through communication with food manufacturers, sensor technologists and consultants and aims to detail the UK capabilities in contaminant sensing in food.

Primary Objective The eventual aim will be to provide to the UKTI a report that can showcase the UK strengths in food sensing in its current state and also the capacity for the UK technology base to innovate the market and respond to the requirements of the food industry.

Secondary Objective Creation of publishable capabilities database highlighting UK companies working in food sensing technologies as well as UK academic research groups working in relevant disciplines

METHODOLOGY

Challenges

17

1. The detection of glass fragments in liquid products filled into glass bottles 2. The detection of glass fragments in particulate food products such as nuts or breakfast cereals  3. The detection of plastic in any sort of food product, wet or dry, particulate or homogenous 4. The detection and sensing of fat, gristle, cartilage etc. in meat, prepared meat and poultry products 5. The detection of bone in meat and poultry products and bone in fish 6. The detection insects in fruits and vegetables 7. The quantification of ripeness in fruits 8. The detection of damage and of mould in fruits and vegetables 9. The identification of the wrong product in a package (e.g. fish pie in a meat pie packet) 10. The detection of “natural plant materials which should not be there”, for example stalks in dried fruits, shell fragments in nut products, dense or wet lumps in breakfast cereals   11. The detection of hair and fibre in any sort of food product 12. The detection of metal in any sort of food product

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UK SENSING TECHNOLOGIES FOR CONTAMINATION IN FOOD

Methodology

Resources for this report have been gathered through a combination of desk research, Internet searching, communication with food industry manufacturers (through the Biosciences community), developers of food sensing technologies and relevant consultants. A full list of organisations assisting in the study are gratefully acknowledged and can be found in Annex 1: Inputs to this study The first stage of the project has been to identify the key challenges in food sensing, 10 were initially suggested by the UKTI - further challenges were identified during the consultation procedure. The next stage has involved communication with food manufacturers to see how currently these challenges are being met. Potentially useful technologies were highlighted in these discussions and companies working in these areas were contacted for their input. The final stage of consultation was through the running of an interactive workshop where food industry experts, technologists and membership organisations were invited to attend to discuss a draft report prepared by the Knowledge Transfer Network This data from the food manufacturers is shown on pages 17 – 46. The methods used are displayed graphically - key comments made were also extracted. •

Provide a comprehensive study of the challenges faced by food manufacturers

•

Identify key technology areas to meet the challenges

•

Promote opportunities for sensor companies in the food sector

•

Provide a map of UK capability in the contaminant sensing sector

•

Provide a networking opportunity for interested parties

The final report will be made available on the Knowledge Transfer Network website – freely downloadable for all interested parties, who could include: •

Sensor companies with an interest in non-destructive evaluation in food processing

•

Food processing companies who wish to investigate options for detection

•

People working in linked sectors with an interest in foreign body detection

CURRENT APPROACHES

Current Detection Approaches

19

There are a few important qualifiers that a detection scheme should be compared against ultimately determining whether it is appropriate for its purpose. The respondents to the questionnaire were asked to consider the following qualifiers. The cost of a device is always a concern for manufacturers. High installation costs can sometimes be countered by low maintenance costs. However, it should be noted that the price of safety infractions can be very high not only in fines, but in recalls and loss of consumer credibility. The ease of use covers how complicated the device is to operate and how easy the results are to interpret. This is linked strongly with cost – if a team of technicians are required to operate, monitor and maintain the device then it may become economically non-viable. The sensitivity of the device will determine how small a foreign contaminant can be discovered and how accurately a characteristic can be measured. This is clearly an important feature as small shards of glass for example can be just as dangerous and large chunks. The speed of a measurement will determine the throughput of food to be checked. Slow time-consuming measurements may end up revealing more accurate results but the time lost may not be worth it, and vice versa a very quick machine that has very high throughput but misses every other object will not be wanted. Speed also encompasses how quickly results take to be analysed; can they be done on sight? Do they need a lab? The specificity of the device will determine whether it is capable of identifying specific information about a contaminant. For example, can it tell the user exactly what type of plastic is in my food? Information such as this is invaluable when locating the source of a contamination – as this can save manufacturers vast amounts of money in lawsuits, shorter shut down periods etc. What is the size of the detector? The platform for the sensor device can vary from a large factory based scanner, a hand held device, mobile phone integrated sensor, on product sensor (a sticker for example). There are obviously advantages for more discreet sensors in food production locations where space is at a premium. Additional extras: are there unique properties to the device that aren’t covered above, can it measure more than one contaminant? Penetration depth? Can it be retrofitted to existing lines? – a large barrier to entry in this market, etc. The following pages provide some detail on the technologies currently being used, along with their advantages and disadvantages. They are divided into off-line techniques, on-line techniques and potential techniques for innovation that aren’t yet in wide scale use.

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UK SENSING TECHNOLOGIES FOR CONTAMINATION IN FOOD

Current approaches Electromagnetic spectrum

The approaches identified are separated into on-line and off-line techniques, they are assessed based on their technological capabilities, their applicability to food contaminant sensing both for liquids in a pipe and particulate food on a conveyor, pros and cons and (if applicable) the UK capabilities For off-line techniques, comment is not made on their applicability to pipe and conveyor - they are included for completeness.

As many of the techniques listed below are based on either the absorption of scattering of parts of the electromagnetic spectrum, it is perhaps useful to remind the reader where the different regimes lie.

Figure 7. The electromagnetic spectrum, taken from Ref. [15]

15. http://www.physik.uni-kl.de/en/beigang/forschungsprojekte/

ON-LINE TECHNIQUES

On-line Techniques

21

X-ray imaging

X-ray imaging uses the absorption / transmission of X-rays to produce images. These images relate to the cross-sectional density of the material being probed. Both two and three - dimensional images can be constructed using tomographic imaging. Whilst some manufacturers may express concern over the quality of food after being subjected to X-rays – the World Health Organisation (WHO) have confirmed that food radiation levels up to 10,000 Sv do not affect food safety or nutritional value - doses used in inspection technologies are significantly lower than that. Due to the ability for X-rays to differentiate materials of differing densities, X-ray imaging can be used to identify contaminants such as metal, stone, glass, dense plastics and calcified bone. These machines are commonplace in food inspection lines due to their low maintenance needs and the relatively easy interpretation of results. The future for Xray imaging could include the incorporation of material discrimination and fat analysis into one system. The sensitivity and range of application of the X-ray inspection methods could be increased by the addition of energy sensitivity, allowing unique identification between thickness and material changes, and thus increasing the contrast of low absorption materials such as plastics and organics. The benefits of using energy X-ray sensitive detectors to detect impurities is well understood, but it has probably not been adopted for in-line food inspection as the existing technology using CdTe or Ge is prohibitively slow and too expensive.

Applicability to liquid in pipes Due to the low absorption cross-section of materials available for industrial food processing pipework – the application of X-ray imaging systems through pipes is not unusual. There exist on the market pipeline X-ray systems for the continuous inspection of pumped products – suitable for fluids, semi-solid products such as sauces and fruit preparations.

Applicability to particulate food on a conveyor X-ray systems are well suited for quickly identifying abnormalities in line product products. The image processing and rejection decisions can be made automatically with pattern recognition software of by human monitoring in a way similar to airport package monitoring.

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UK SENSING TECHNOLOGIES FOR CONTAMINATION IN FOOD

Table 3. X-ray imaging usefulness in the food sector [16]

PROS AND USES

CONS AND LIMITATIONS

Can penetrate deep within the sample travelling through packaging.

The X-ray beams are ionising – this causes little to no damage to the food under inspection but can cause health problems for operators accidently exposed to the beam.

It is a non-destructive technique, non-contact technique Capabilities: • Metal • Glass • Stones • Calcified bones • PVC plastic • Teflon • Ceramics or concrete • Flavour / sugar clumps • Missing product Applicable for ready meals, prepared foods, meat, bakery products, cereals, dairy foods, confectionary, vegetables, fruit, cosmetics.

Limitations: • Low-density plastics • Thin glass • Low-density stones • Insects • Wood • Hair • Cardboard • Paper • Non-calcified bones

Linked sectors Healthcare: Perhaps the most common use of X-ray imaging is in medical healthcare where 2D and 3D images are constructed of patient interiors. Hard X-rays are also used in the medical treatment of cancer. Material Science: Hard X-rays are often used in material science for non-destructive testing of crystallographic information etc. Astronomy: There are various sources of X-rays in the Universe which are studied by scientists, detectors for hard radiation are used in this sector. Security: A very common use of X-ray imaging is in security applications to see through packaging and luggage for non-destructive security testing.

16. http://www.loma.com/lo_xray_guide.shtml

ON-LINE TECHNIQUES

23

X-ray spectroscopy X-ray spectroscopy uses the scattering or absorption of X-rays to provide qualitative information on the electronic structure of the sample. Absorption and scattering of X-rays gives a material dependent spectrum allowing for identification and composition of various materials. X-ray spectroscopy can be found in off-line and on-line solutions to food quality testing. Unlike X-ray imaging however the technique often requires more complicated detection systems than X-ray imaging by use of X-ray dispersive optics or solid-state X-ray energy analyzers. Some examples from Ref. 23 of X-ray spectroscopy are EDAX analysis to determine phosphorous content of potato starch and also as trace element detection for specific contaminant detection. A further example of ham identification is detailed in Ref. [17] – high flux synchrotron radiation identified signatures in cured ham unique to the curing process helping to establish a test against ham fraud.

Applicability to liquid in pipes For spectroscopy techniques in the photo absorption regime, X-rays are often tuned to core energy levels of electronic structures – this often puts the energy of the X-rays at the low energy end that severely limits the penetration depth. Spectroscopy through pipes and semi solid liquids would be difficult to achieve [18].

Applicability to particulate food on a conveyor An easier application for X-ray spectroscopy measurements would be in particulate solids on a conveyer, X-rays would only penetrate minimally into the surface and collection and analytical time may however severely limit throughput.

17. http://www.esrf.eu/Apache_files/Newsletter/ESRFNewsSep2010.pdf 18. There are spectroscopic techniques higher in energy, although the application of these would be fraught with difficulty for interpretation.

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UK SENSING TECHNOLOGIES FOR CONTAMINATION IN FOOD

Table 4. X-ray spectroscopy usefulness in the food sector

PROS AND USES

CONS AND LIMITATIONS

Very specific method of identification

Spectrum analysing sources require complicated equipment.

Can penetrate deep within the sample, travelling through packaging Scans can take longer than X-ray imaging Capabilities: • Metal • Glass • Stones • Bones (only calcified) • PVC plastic • Teflon • Ceramics or concrete • Flavour / sugar clumps Missing product

Energy dispersing CCDs or solid state detectors are expensive Only reasonable small areas can be examined at a time Limitations: • Low-density plastics • Thin glass • Low-density stones • Insects • Wood • Hair • Cardboard • Paper

Applicable to ready meals, prepared foods, meat, bakery products, cereals, dairy foods, confectionary, vegetables, fruit, cosmetics. Linked sectors Material Science: soft X-rays are often used in material science for non-destructive testing, electronic structure analysis, magnetic information, compositional analysis etc. Astronomy: There are various sources of X-rays in the Universe that are studied by scientists, detectors for hard radiation are used in this sector. Healthcare: In pharmaceuticals X-ray spectroscopy is routinely used for quality control of catalyst concentration and foreign matter.

ON-LINE TECHNIQUES

25

Raman spectroscopy Raman Spectroscopy is a method of vibrational spectroscopy long known to the condensed matter physics world and is a technique which provides information on rotational and vibrational modes in materials – as such provides ‘fingerprint’ information of substances that are unique to that substance. In Raman spectroscopy, a sample is illuminated by a monochromatic light source, this light is used to promote electrons from vibrational states into higher level virtual states, as the electron falls back into its ground state, light is radiated which is specific to that vibrational state (Figure 8). The scattered light is then measured on a detector. Summing over all the present vibrational states results in a spectrum that is unique to a substance. In food technologies, Raman spectroscopy may be used as a tool for quality control, for compositional identification (fatty acid composition, fish and meat muscle quality) or for the detection of adulteration, as well as for basic research in the elucidation of structural or conformational changes that occur during processing of foods (changes in proteins, water and lipids that occur during deterioration), Refs [19 and 20].

Applicability to liquid in pipes Obtaining Raman spectra from liquids or semi-solid liquids is possible wherever there are molecular bonds – fast moving, inhomogeneous samples however will prove difficult to obtain a good Raman spectrum for.

Applicability to particulate food on a conveyor The speed of data collection can again cause difficulties for on-line detection, but it is classed here as an online technique due to its abilities as a remote detection scheme. Another issue may be the small sample volumes obtainable – as to the best of the authors knowledge, widefield Raman imaging is not a well established technique [21].

19. Raman Spectroscopy a promising technique for quality assessment of meat and fish: A review, Food Chemistry, 107, 1642 (2008) 20. The applications of Raman spectroscopy in food science, Trends in Food Science & Technology, 11, 361 (1996) 21. There are methods, however, available for building Raman images, but these often rely on point by point scanning and can be very time consuming, Raman Imaging: Techniques and Applications. Arnaud Zoubir, Springer Series (2012)

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Table 5. Raman usefulness in the food industry

PROS AND USES

CONS AND LIMITATIONS

Non-contact

No commercial solutions for food

Non-destructive Can be enhanced greatly using nanostructures to provide surface-enhanced Raman scattering which can be capable of single molecule detection levels

Fluorescence can be a problem for detection. Hard to develop wide field solutions

Very weak response to water Linked sectors Healthcare: Raman gas analysers are used in medicine for real-time monitoring of anesthetic and respiratory gas mixtures during surgery. Pharmaceuticals: identification of pharmaceutical constituents can be made using Raman. Security: Raman scanners have found a large market in airport security due to their fingerprinting abilities [22].

Figure 8. Example of Raman spectroscopy of native starches from Ref. [23]

22. http://physicsworld.com/cws/article/news/2012/feb/07/raman-technique-peers-into-cabin-baggage 23. Characterization of Irradiated Starches by Using FT-Raman and FTIT Spectroscopy, Journal of Agricultural and Food Chemistry, 50, 3912 (2002)

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Visual Inspection Visual monitoring of foodstuffs uses humans as resources to watch the food move past, any thing that doesn’t conform to the standard is taken from the production line. The definition of non-conformity is vital to be established from the outset. Many production facilities set out the criteria for non-conformity see Refs [24] for examples.

Applicability to liquid in pipes Only very obvious problems can be identified using visual inspection of food and liquids in pipes, more often that not - visual inspection is enhanced by providing the use of X-ray technology for the inspector to see through obstructing pipes.

Applicability to particulate food on a conveyor Visual identification is easier for discrete items on a conveyer than in a pipe, again is assisted by the use of non-standard imaging techniques to assess uniformity. Other sensory inspection could help here, such as smell or touch. Table 6, Visual inspection usefulness to the food sector

PROS AND USES

CONS AND LIMITATIONS

Non-destructive technique

Very resource intensive

Can be used as a monitor for many defects in one

Highly variable outputs

24. Guidelines Procedures for the Visual Inspection of Lots of Canned Foods for Unacceptable Defects, CAC/GL 17

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Infrared techniques Near Infrared (NIR) spectroscopy uses the different absorption conditions of different compounds to analyse the constituent elements of a sample. The NIR region extends – roughly – from 800 nm to 2500 nm and is thus very well suited for the detection of organic compounds. The technique uses transition probabilities of photons to map the states in a material. In the food industry NIR spectroscopy has been used for many years to determine the food quality in an accurate, non-destructive and rapid way. Due to its sensitivity to organic content (water, sugar, acids etc.) - It can be used to determine moisture, fat and protein content and other components that impact on product quality and safety. some firms are currently marketing NIR based sorting and grading systems for use with citrus, pome and stone fruits As well as being able to detect the presence of organic content the technique can be used to fingerprint what the content is (useful for pathogens, allergens etc) and with plastics being composed of organic chains, plastic contaminants can not only be located, but also identified. MIR is very rich in the information it provides for organic materials in terms of the fine structure in the spectrum.

Applicability to liquid in pipes There are product solutions of pipe-mounted NIR liquid process cells for monitoring. NIR spectroscopy, however, suffers from strong absorption in water, as such applicability to liquids in pipes may be limited and the penetration depth of the NIR beam would severely limit the diameter of the process pipe.

Applicability to particulate food on a conveyor Particulate food on a conveyer is well suited for NIR inspection and there are products that analyse the NIR spectrum of food and beverages. Quicker measurements are available by sing FT-IR spectroscopy (see one of the following next sub-section).

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Table 7. NIR usefulness in the food industry

PROS AND USES

CONS AND LIMITATIONS

Easier maintenance than X-ray machine

Short penetrating length

Uses non-ionising radiation, i.e. safer than X-rays Non destructive Real-time measurements Little or no sample preparation Due to its sensitivity to moisture, proteins, fats and sugars it is ideally suited for the dairy industry

InGaAs or PbS detectors less sensitive then visible CCDs. The strong absorption in water has historically limited the use for assessment of fresh produce Calibration limitations

Good applicability to fruit Good applicability to identifying presence of organic content Linked sectors Astronomy: spectral information can tell astronomers about star types and stellar formation and processes. Healthcare: used to measure oxygen content of blood, and also can be used on the skull to provide information of blood flow related to neural activity as a partial replacement for fMRI (functional MRI) Materials: can be used to measure film thicknesses for optical coatings. The technique is closely linked with hyperspectral imaging (HSI) described in the following section, due to its proximity in the EM spectrum, HSI is where optical measurements are combined with imaging to provide images containing not only spatial information but wavelength information. The difference in these technologies is often in the detections scheme-in NIR spectroscopic information is often obtained using dispersive elements whereas in HSI, the detector is constructed as to observe many wavelengths simultaneously.

FT – IR spectroscopy FT-IR (Fourier transform infrared spectroscopy) is considered a more sensitive and robust technique over dispersive NIR techniques described above by its lack of diffraction grating to separate out frequencies – instead interferograms are collected by a interferometer-like setup which represent the Fourier transform of the absorption spectrum.

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FT-IR has the following advantages over dispersive and filter methods of IR or NIR methods: Table 8. Advantages of FT-IR over dispersive IR, from Ref [25]

PROS AND USES It is non-destructive
 Solids, liquids and gases can be analyzed
 It is possible to easily identify and distinguish between many organic compounds and inorganic compounds
 Precise measurement method that requires no external calibration
 FTIR measurements can be made within seconds
 Optimal sensitivity – detectors are more sensitive and the optical throughput is higher. FTIR can identify small concentrations of contaminants. Mechanical simplicity – The mirror in the interferometer is the only moving part in the FTIR instrument, therefore making mechanical breakdown minimal. Simultaneous analysis of multiple gaseous compounds

25. http://www.aircomp.com/blog/advantages-of-ftir-over-dispersive-methods-of-infrared-spectral-analysis/

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Hyperspectral imaging The hyperspectral imaging (HSI) method combines digital imaging with spectroscopy for give detailed information across multiple ranges of the EM spectrum. Unlike single source detection systems, hyperspectral imagers collect data from across the electromagnetic spectrum. Hyperspectral imaging can be perceived as an extension of multispectral imaging (MSI); while multispectral imagers look at light from up to 10 wavebands, hyperspectral imagers are capable of obtaining information in a more continuous fashion, over 100 wavebands. Data are therefore not stored as two-dimensional images but instead as cubes, where the third dimension spans the wavelength range of the detector. These cubes are unique for every produce and serves as a reference for the sorting procedure. The use in food can be in using the ‘fingerprinting’ ability to determine what the constituents of the passing food are and whether it should be there. Indeed there exist some commercial solutions already.

Applicability to liquid in pipes Many of the disadvantages of liquid in pipe sensing for NIR are shared with HSI.

Applicability to particulate food on a conveyor HSI lends itself well to conveyor inspection lines - the advantage of simultaneous acquisition across many wavelengths allows quick gathering of vast amounts on information, see for example chicken carcass inspection Ref. [26].

PROS AND USES

CONS AND LIMITATIONS

Non-contact, non-destructive

Few commercial solutions

Due to the multi-wavelength approach vast amounts of data are recorded simultaneously

Expensive detection systems for HSI

Large area detection Applications in differentiating organic components

Limited penetration length Large storage capabilities required

Extraneous vegetable matter Stones and shells Meat and poultry contamination

26. Hyperspectral waveband selection for contaminant detection on poultry carcass, Opt. Eng. 47(8), 087202 (2007)

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Linked sectors Due to its fingerprinting and identification capabilities hyperspectral imaging can find uses in various linked industries. Astronomy: mapping the physical properties of cosmic hot gas. Security: in forensics hyperspectral imaging can be used for detection of forged documents and fingerprints at crime scenes. Environmental monitoring: Hyperspectral imaging can be used to monitor vegetation and has been equipped to UAVs to detect large images. Medicine: extent of burns and bruises below the skin of the human body, skin imaging for the diagnosis of skin cancers. In pharmacology it can be used discern the makeup of drugs that look identical to the naked eye and conventional imagers.

Figure 10. The image on the left shows raisins with impurities in between (paper, plastic). The blue and green arrows point two spectral positions of raisins. In the graph on the right it can be seen that points with similar color also have similar spectra behind. The red arrow points a different color. Taken from Ref. [27].

27. http://www.perception-park.com/what-is-chemical-color-imaging.html

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Optical sorting Optical sorting methods use advanced image recognition equipment to automatically identify shapes, size, color and patterns of items that do not fit set parameters, current systems. The spectral information / images could be from any other optical sensor techniques shown above – more often than not however, they are based on monochromatic or tri-chromatic cameras. Optical sorters are widespread in the food industry due to its in-line, non-destructive and low human resource use. Compared to manual sorting, which can be is subjective and inconsistent, the non-reliance on human resources helps improve quality of products, maximize throughput, increase yields and reduces labour costs. From Ref 28, in meat, it has been used to characterize muscle colour, marbling, maturity and muscle texture. In other applications sorting technologies have been used in agricultural products such as fruits, vegetables or grain. In general, and optical sorting system is composed of four major components; the feed system, the optical system, image-processing system and the separation system. The optical system can be integrated with advanced technologies such as hyperspectral sources which as a great deal of functionality to the system.

Applicability to liquid in pipes The applicability and usefulness in pipes is essentially the same as that for inspection by humans, except it takes out the uncertainty and random errors associated with human monitoring.

Applicability to particulate food on a conveyor See above

28. Irudayaraj, J and Reh, C. (2008) Nondestructive testing of food quality, Blackwell Publishing Ltd.

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Table 9. Optical sorting usefulness in the food industry [29]

PROS AND USES

CONS AND LIMITATIONS

These systems can be very specific

Due to the integration of robotics, can be reasonably expensive.

Automation means that human resource costs are low 100 %, on-line inspection Applicable to: Seeds

Can give information of the wrong shape and size, but not applicable to all types of defects Limited to transparent / surface incidents

Coffee Fruit Grain Nuts Linked sectors

Pharmaceutical: in this sector optical sorting is used for optimizing the end products of pharmaceutical products ensuring quality, efficient and reliability. Industrial: can be used for automated machine building tasks, waste recycling, tobacco processing. A comparison of RGB imaging, NIR spectroscopy, multispectral imaging and HSI are shown below for a comparison (adapted from Ref. [30]). Table 10. Comparison of RGB, NIR, MSI and HSI techniques

ATTRIBUTE Spatial information

RGB

Sensitivity to minor components

MSI

HSI

P

P

P

Limited

P

P

Limited

P

P

Spectral information Multi-constituent information

NIR

Limited

P

29. http://www.buhlergroup.com/global/en/process-technologies/optical-sorting.htm#.Uut1lHm4ml 30. Potential application of hyperspectral imaging for quality control in dairy foods, Gowen et al, Image Analysis for Agricultural Products and Processes, 65, (2011)

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Terahertz imaging Terahertz (THz) radiation lies in-between microwave and the far infrared on the EM spectrum generally with a wavelength range of between 100 µm and 1 mm corresponding to frequencies of 0.3 to 3 THz. Unlike microwave radiation it can penetrate a wide variety of non-conducting materials. Non-destructive evaluation, the energy of the THz band is 1 – 10 meV. T-rays are inherently sensitive to water; they are very suitable for moisture detection. Transparent to opaque materials such as plastic, fabric, ceramic and paper so the technology has the ability to see through some packaging materials. THz has applications in food technology due to its strong interaction with water. Moisture content can be used to infer different properties of a foodstuff – fat content, ripeness etc. Its ability to see through plastics and card also make it perfect for NDE of packaged food

Applicability to liquid in pipes High water content materials are almost completely opaque to THz radiation, this in conjunction with possible metal piping means that THz imaging and spectroscopy has very limited uses to liquid phase food.

Applicability to particulate food on a conveyor For less water intense materials, the opaqueness of water to THz can provide a wealth on information for moisture detection. Its ability to see through paper, plastic can check for missing items on a conveyor. Table 11. THz usefulness in the food industry

PROS AND USES

CONS AND LIMITATIONS

On-line, non-destructive technique

Metal and polar liquids (such as water) completely opaque to THz radiation

Many more materials are transparent to THz radiation (as compared with IR) Non-ionising.

THz radiation cannot penetrate metal Expensive sources and detectors are major obstacles for commercial devices

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Linked sectors Due to the ability of THz radiation to penetrate common packaging and clothing materials there is interest from sectors such as: Healthcare: unlike X-rays THz radiation is non-ionising and therefore a safer alternative for medical applications. It also has the ability to distinguish areas of different density and water content. Security: the non-ionising properties of THz radiation also makes it an attractive method for concealed weapon detection through clothing, the additional method of THz spectroscopy allow the unique fingerprints of substances to be exploited and identify concealed substances. Manufacturing: uses in manufacturing, quality control and process monitoring due to the transparent properties of cardboard and plastic, the inspection inside packaged goods can take place.

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Microwave detection Microwaves are no stranger to the food industry – the ease at which microwaves are generated coupled with the strong absorption by water make them ideal for microwave heating devices. Detection systems that operate in the microwave part of the spectrum are far lower power - Ref. [1]. Microwave imaging is uncommon as the large wavelength for small objects result in diffraction effects and a severely limited image when compared with X-ray imaging for example. Microwave detection systems instead rely on measuring the transmitted microwave field passing through a product and the local variation in dielectric properties between foreign objects and the product. Dielectric discontinuities are seen as absorption change of phase. Similar to THz radiation, though possessing higher penetration depths microwave radiation has a wavelength range of between around 1 cm and 30 cm corresponding to a frequency range of 200 MHz to 300 GHz. Active microwave technology for this area is much closer to commercialization than THz equipment, with sources and detection methods well established from areas such as telecommunication. Unlike microwave ovens, the radiation used in low power and more similar to an Xray imaging set-up. Additionally due to its response to water, microwave wavelengths have been proposed for use in measuring water content for ripeness determination, see Ref. [62].

Applicability to liquid in pipes A Swedish company – Food Radar – has commercialized a product using microwave radiation; the transmission of the microwave radiation is dependent on the permittivity of the transmission medium. Foreign objects change a materials permittivity and the detected radiation can thus be monitored for contamination – applicable to liquids and emulsions. It is claimed that glass (10 mg pieces), metal filings (5 mg), plastics, stones, wood and other organic materials can be detected with microwave techniques,

Applicability to particulate food on a conveyor Microwave sensing can still be applied to food on a conveyor provided they are not in metal packaging – unpackaged, wood, plastic etc. But the technique is best suited for homogenous, piped foods if possible.

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Table 12. Microwave radiation usefulness in the food industry

PROS AND USES

CONS AND LIMITATIONS

Non-contact, non-destructive

No UK commercial solutions

Very wide range of contaminant materials detectable by their microwave impedance.

Not ideal for imaging

No limits on speed of flow through the food-processing system. Good for metal, glass, stone and voids. Unique in its ability to measure wood, stones, plastics, shells, rubber, seeds, paper Linked sectors Astronomy: the microwave background in the Universe provides evidence of the forming of the universe and various other extra-terrestrial microwave sources. Communication: Many communication protocols operate in the microwave range. An advantage of microwaves over radio waves is that the microwaves have a higher frequency and therefore can encode more information. Healthcare: There are examples of microwave imaging being used for the detection of breast cancer

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Ultrasound Ultrasound uses the transmission and reception of high frequency, low power ultrasound (pressure waves) to locate foreign bodies by being able to differentiate discontinuities in acoustic impedance by analysis of original and reflected waves. In doing so, can determine composition, structure and physical state. Ultrasound has been used in food technology for many years [31]. It can be divided into two areas; high frequency, low power and low frequency, high power, the low energy is used for quality assurance and process control and high power ultrasound is an emerging technology area for modification of food (not the focus of this report). For process monitoring, recent publications detail the use of ultrasound on canned foods, Refs [32,33]

Applicability to liquid in pipes Impedance matching is far easier for liquids in pipes than discrete objects as better contact can be made between transducer and the object of interest. The transducer can assume various geometries and the pipe itself can act as the transducer as it will always be in contact with the food material - Ref. [34]

Applicability to particulate food on a conveyor Difficult to achieve in practice due to the requirement of contact, although there have been proof of principle demonstrations of ultrasound applied to canned foods and cheese, Refs [35-36]. Detection is more difficult in inhomogeneous samples.

Linked sectors Whilst high-power ultrasound has many applications in industrial processing, low power ultrasound is generally used for non-destructive evaluation (NDE) an has many applications: Healthcare: 2D and 3D imaging are possible in human and animals using ultrasound and is an attractive technique due to its lack of ionizing radiation and relatively inexpensive and portable equipment. Industrial processes: used extensively in the aerospace industry for evaluating cracks and detects in composites and metals. Can also be used for materials such as wood, concrete and cement. Security: Commonly used in underwater applications as SONAR for range finding and object location

31. Applications of Ultrasound in Food Technology, Acta Sci. Pol., Technol. Aliment. 6(3), 89 (2007) 32. Detection of foreign bodies in canned foods using ultrasonic testing, International Food Research Journal 19(2), 453 (2012) 33. Online Detection of Contaminants in Packaged Foods with Ultrasound using Signal and Image Processing and Soft Computing, Mittal and Basir, IEEE (2009) 34. Ultrasound in Food Processing, M. J. W. Povey, Springer Books () 35. Detection of foreign bodies in canned foods using ultrasonic testing, International Food Research Journal, 19, 543 (2012) 36. Ultrasound detection and identification of foreign bodies in food products, Food Control, 12, 37 (2001)

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Table 13. Ultrasound usefulness in the food industry

PROS AND USES

CONS AND LIMITATIONS

Rapid

No commercial solutions

Non-destructive and on-line

Good contact required between transducer and object to reduce impedance mismatch, difficult for online systems.

Low power usage and safety Ultrasound can be coupled to liquids in pipes very well. Well suited for, large acoustic impedance contrasts, missing items. Well suited for liquids in glass bottles

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Magnetic Separation Magnetic separation can be used to filter out the “tramp” iron that can find its way into a production from fields or processes. Low intensity magnetic fields are applied to the moving sample of solid or liquid food. The field may be applied from a permanent magnet (high field rare-earth magnets such as SmCo5 or Nd2Fe14B) or electromagnets.

Applicability to liquid in pipes The effectiveness of magnetic separators is reduced in damp food; the technique however is effective in free flowing liquids

Applicability to particulate food on a conveyor Embedded metal contaminants will remain embedded in large, dense food objects. Instead the ideal situation for magnetic separators are small, discrete foodstuffs like nuts, flour etc. Table 14. Magnetic separation usefulness in the food industry

PROS AND USES

CONS AND LIMITATIONS

Non power consuming, passive detection

Invasive and requires maintenance

Simple to operate

Substance must be magnetic

Applicable for some metals and can remove objects as small as a few microns.

Large magnetic fields can be hazardous to health

Can be used well for cereals, nuts, flour

Not applicable to non freeflowing or damp mediums

Linked sectors Industrial processes: such as mining iron, removing useful magnetic components from scrap etc.

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Metal detection In standard metal detection techniques, an RF signal transmitted by the detector is compared with the one received. Non-metallic material passing through the RF field does not distort the RF field. Metal passing through the signal fields however will distort the normal pattern of the electrical fields. Distortion limits can be set to detect very small metal inclusions.

Applicability to liquid in pipes Solutions exist for pipeline metal detectors as RF signals can be used through pipes and metal work. The contamination being present in a liquid phase does not complicate the detection significantly.

Applicability to particulate food on a conveyor As RF signals can penetrate deeply through a medium – large, dense objects can be screened by metal detection techniques. Table 15. Metal detection usefulness in the food sector

PROS AND USES

CONS AND LIMITATIONS

High level of sensitivity

Only detects conductive materials

Non-destructive Metals need not be ferrous

Biased towards magnetic materials Many food products are conductive

Linked sectors Archeology: both as a hobby and industrially metal detectors are used to locate metal objects of interest underground. Military: a very common use of industrial metal detection is in the security sector capable of measuring very small metal objects.

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Sampling Sampling techniques involve sampling parts of the production line as to get a statistical idea of the quality of the entire production line. The sampled section of the line can then be subjected to further off-line tests to check for conformity.

Applicability to liquid in pipes Sampling can be performed for both liquids and particulate objects. Careful consideration must be given to the sampling frequency as under sampling can result in poor coverage and oversampling can be time inefficient and expensive.

Applicability to particulate food on a conveyor See above Table 16. Sieving and sampling usefulness to the food sector

PROS AND USES

CONS AND LIMITATIONS

Can perform any measurement on the sample once the foodstuff has been samplede

Statistical approaches can easily overlook contaminants

Linked sectors Visual inspection, sieving and sampling are used for all industries as at very least a check that automated processes are performing correctly.

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Electrical impedance Perhaps one the most simple measurements one can perform to locate foreign objects is to utilize the change in impedance inherent with a foreign object contamination event. For an AC signal, the change in resistance, capacitance and inductance are related to the complex impedance of the sample, which affects the signals magnitude and phase. Changes in a materials complex impedance will result in measurable signal changes which can be used as an indicator of contamination. Certain physical changes in food structure and state can have an effect on the electrical properties. As a couple of examples electrical transport anisotropy of meat was able to determine the ageing of meat, Ref. 37.

Applicability to liquid in pipes In Ref. [1] is shown an example of how an electric system tuned close to resonance can act as an effective foreign body locator in piped foods. in a steady flow the resistance should be fixed – foreign objects would affect the resistance of this flow. The sensitivity of this device comes from its proximity to resonance – and thus its susceptibility to any change in the resistance. Shown in Figure 11 is an example of the detection of small non-metallic impurities by phase measurements. Foreign objects alter the output electrode signal close to the resonant frequency of the system resulting in a large output change (again from Ref. 1).

Applicability to particulate food on a conveyor One current application of impedance-based system is designed to detect damage in bottles (a key cause of glass contamination) – the system applies a high voltage electric field to four points around the circumference of the bottle, any damage shows itself as a change in the impedance when compared to a reference sample and is capable of detecting hairline cracks, Ref. [1]. Table 17. Electrical usefulness in the food industry

PROS AND USES

CONS AND LIMITATIONS

Non-destructive

No UK commercial use

Simple experimental set-up Can detect anything that has different impedance properties to its surroundings, so applicable to glass, rubber, plastic, metal etc.

37. Electrical impedance probing of the muscle food anisotropy for meat aging control, Food Control, 10, 931 (2008)

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Linked sectors The electrical properties of materials are used across many industries as it can give detailed information on the microscopic behavior of the charge carriers.

Figure 11. Response of the impedance sensor to non-metallic foreign bodies taken from Ref [1]

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Off-line / Lab-based Techniques

Biosensors Biosensors are devices that detect an analyte that combines a biological component with a physiochemical detector component. In the food industry these sensors are often associated with the detection of pathogens and food toxins. Although may have applications where the analyte is not a pathogen but another indicator of interest, ripeness for example. The potential uses for these are very broad. Advances in sensor production mean that these can be made very cheaply. Table 18. Biosciences usefulness in the food industry 38

PROS AND USES

CONS AND LIMITATIONS

Wide range of detectable contaminants, E-coli, MRSA, toxins representative of animal contact, moisture, allergens

Tend to be for chemical contamination testing Contact method

Can be integrated into packaging /stickers, see for example Ref. [38] Linked sectors Taken from Ref [39] Healthcare: increasing lifetimes with increasing ailments, increasing affluence and expectation of well-being are expected over all timescales and with the large functionality of biosensors this is an important driver. Industrial processes: Energy costs and resource efficiency are issues that will extend to the long-term Environmental: Legislation and public opinion, global climate are medium and long-term drivers. Much work is being done in this area to develop generic biosensors that can detect a range of contaminants in water / air necessitated by EU legislation. Security: one-off events and global conflict can initiate both shortterm needs for example (for anthrax detectors) and longer-term policy changes.

38. http://www.ripesense.com 39. UK Sensor Company Capability and Opportunities Study, To be published 2014, ESP KTN

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Nuclear magnetic resonance Nuclear magnetic resonance (NMR) uses RF excitations to cause nuclei to precess in the presence of a magnetic field, the relaxation of the nuclei give great detail on the content of the sample and its environment. Due to the historic use in the medical industry this technique is very well suited for meat analysis. Ref [40] gives a detailed overview of where the technique is currently being employed by the food industry – although still limited to the academic world due to high equipment costs and resource inefficiency. Whilst there exist many commercial solutions, these remain expensive and bulky due to the requirement of high fields. Earth field NMR machines do exist but fail to deliver resolutions that are required for industrial practices. The UK academic community has ample access to NMR machines often based in material science department at Universities such as Warwick, St Andrews, Cambridge, Sheffield, Durham, Nottingham, Glasgow, Oxford, Birmingham, Queen Mary University of London, Imperial College London, York, Bristol, Southampton, Liverpool, Newcastle, Sussex Table 19. NMR usefulness in the food industry

PROS AND USES

CONS AND LIMITATIONS

Very sensitive

Can be very expensive

Ideal for meats / organic tissue

Resource heavy for powerful magnets

Non-contatc, non-destructive

Samples must remain stationary

Linked sectors The technique of NMR has applications in many other sectors such as: Material science: NMR spectroscopy can be used to study the chemical structure of a material, time domain NMR spectroscopy is used to molecular dynamics of systems by matching the RF frequency to element of interest. Healthcare: a very important application for NMR is that of magnetic resonance imaging (MRI) - the 3D imaging and analysis of human and animal tissue has revolutionized medical diagnosis and is perhaps the best known use of the technique.

40. Davenal et al, Advances in Magnetic Resonance in Foods (1999) p. 272

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Figure 12. NMR spectra from beef and horse meat samples, taken from Ref. [41]

Figure 13. Slices of decomposing worm-eaten apple, from Ref. [42]

41. http://www.oxford-instruments.com/ 42. http://alisi.isibrno.cz/en/nuclear-magnetic-resonance

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Microscopy Microscopy uses focused light / electrons to probe very small sample volumes, scanning electron microscopy for example, boasts a resolution of around 1 nm, as such it is not often used as a alert indicator for foreign contaminants in food. Its used in food is instead because it can be used to identify the origin of a contaminant. The origin can be identified through a range of microanalyses; topological microscopy (by identifying very small surface marks), and compositional microscopy (EDAX microanalysis) to identify what the contaminant has been in contact with and through this information, identify where the contamination has come from. As an example of the techniques usefulness Figure 14 from Ref. 43 shows a failed weld repair on a tubeplate from a piece of food processing equipment, demonstrating a different metal composition in the welded area. EDAX microanalysis showed the presence of titanium in the welded area, absent in the rest of the sample, and indicating that the wrong welding rod had been used for the repair. Table 20. Microscopy usefulness in the food sector

PROS AND USES

CONS AND LIMITATIONS

Can be highly specific in terms of origin of contamination

Can only probe very small areas so would only be used once contamination is suspected

Linked sectors The highly specific nature of microscopy means that it has many crosssector applications, such as pathology, fundamental science, archeology, forensics etc.

43. Microscopy for the Food Industry, Royal Microscopy Society, Issue 6, 47 (2007)

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Figure 14. A backscattered SEM image of a failed weld repair described in the text.

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Mass spectrometry In mass spectrometry samples are ionised by high-energy electrons, the fragments are then separated using a magnetic field to analyse the spectrum of the weight (m/Z) of the sample. This spectrum is unique to the sample and can give highly accurate, quantitative information of contaminant levels in a sample. An example of where the high sensitivity and high accuracy characteristics of the technique are useful is in allergen testing for allergens such as egg and milk allergens in baked goods. Traditionally allergen testing would be done using PCR or ELISA assays, which can suffer from false negatives and lack a truly quantitative output. Table 21. Mass spectrometry usefulness in the food sector

PROS AND USES

CONS AND LIMITATIONS

Very specific

Destructive, off-line testing Resource intensive

Linked sectors Environmental: Another sector which requires accurate monitoring of contaminant levels is environmental monitoring Healthcare: Drug analysis and clinical diagnosis use mass spectrometry techniques to fingerprint the constituent atoms. Forensics: The unique fingerprinting ability of mass spectroscopy allows accurate identification of substances to be made.

Figure 15. Example of trace analysis of fruit (taken from Ref 44)

44. Screening of agrochemicals in foodstuffs using low-temperature plasma (LTP) ambient ionization mass spectroscopy, Wiley et al, Analyst, 135, 971 (2010)

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Chromatography Chromatography uses the different speeds in which different substances move through a mobile phase and uses that to separate out the continuants chemicals. Through this separation the method can provide quantitative determination of carbohydrates, lipids, proteins, peptides, amino acids, vitamins, aroma and flavor compounds in a wide variety of foods and food products (from Ref. 45). Table 22. Chromatography usefulness in the food industry

PROS AND USES

CONS AND LIMITATIONS

Can be specific in its identification of contaminant

Sample must be soluble

Quick measurements

Destructive, off-line technique

Linked sectors Environmental: Thin-layer and liquid chromatography can detect pollution compounds and pesticides or insecticide residues. Security: gas chromatography can be used to detect bomb substances, drugs and alcohol Forensics: can be used to compare fibers found on a victim and analyse the dye composition of fibres, RNA fingerprinting, separating and testing histamines and antibodies.

45. Cserhati, T. and Forgacs, E. (1999) Chromatography in Food Science and Technology, CRC Press

OFF-LINE / LAB BASED TECHNIQUES

53

Polymerase Chain Reaction Polymerase chain reaction is a versatile, sensitive and reproducible process that exponentially amplifies a DNA fragments over several orders of magnitude to test organic material for its make-up. The development of real-time PCR using fluorescence means that information can be gathered during the amplification process - not only at the end. Aspects of food quality such as genetically modified organisms (GMOs), allergens and food authentication are of huge current interest to manufacturers as such real-time PCR is a promising technique for addressing these. Speed, excellent detection limit, selectivity, specificity, sensitivity and potential for automation are among the most important advantages of real-time PCR, Ref. 46. Table 23. PCR usefulness in the food industry

PROS AND USES

CONS AND LIMITATIONS

PCR test results report very close to 100 % specificity and sensitivity.

Can take up to an hour to receive results. Offline and destructive testing Only applicable for biological contamination

Linked sectors Healthcare: PCR is regularly used in medicine for genetic testing, for screening, tissue typing, mutation monitoring etc. Forensic pathology: DNA fragments found at crime scenes can be used to fingerprint uniquely suspects.

46. Rodrîguez-Låzaro, D. (2013) Real-time PCR in Food Science, Norfolk, Caister Academic Press

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Enzyme-linked immunisorbent assay The enzyme-linked immunisorbent assay (ELISA) is a technique that uses antibodies and colour change to identify a substance, usually an antigen but could be an antibody. Common uses of the technique are in home pregnancy test kits In the food industry primarily for use in identifying food allergens such as milk, peanuts, walnuts, eggs etc. In the industry the most common and preferred methods for detection are ELISA and PCR. The ELISA method detects the actual allergen protein molecule by binding antibodies to the allergen and ten use enzyme-linked conjugate to create a colorimetric change, from Ref. 47 Table 24. ELISA usefulness in the food industry

PROS AND USES

CONS AND LIMITATIONS

Non-hazardous equipment used, unlike other wet chemical techniques

Expensive

Can detect substances in the parts per million (ppm) range

Variable quality depending on skill of tester Destructive, off-line technique

Linked sectors Healthcare: diagnostic tool for pathogens in medicine, such as the HIV virus.

47. http://www.elisa-antibody.com/index.php?page=food-industry

OFF-LINE / LAB BASED TECHNIQUES

55

ATP Bioluminescence Adenosine triphosphate (ATP) Bioluminescence is a biological reaction between ATP and the enzyme luciferase that produces light that is detectable – the intensity of the light is a measure of concentration. ATP is an indication of life. A pen-like device containing reagents is swabbed in an area and then inserted into a light monitor. The reading in RLU (relative light unit) is an indication of the presence of organic substances. ATP bioluminescence is used in the food industry as an indicator of life and therefore biological contamination. Table 25. ATP usefulness in the food sector

PROS AND USES

CONS AND LIMITATIONS

Reading within seconds

Destructive testing

Cost effective

Measure only of microorganism contamination and not specific for which microorganism

Available commercially, doesn’t require specialist training

Linked sectors The linked sectors are in any industry where live cell cultures need to be quantified as perhaps a hygiene concern.

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Technology Summary Table

PCR OFF-LINE

ELISA MICROSCOPY MASS SPECTROMETRY ATP BIOLUMINESCENCE

ON-LINE SPECTROSCOPY

X-RAY SPECTROSCOPY

OTHER ON-LINE

CHROMATOGRAPHY

MAGNETIC SEPARATION

X-RAY IMAGING NEAR IR OPTICAL SORTING

SAMPLING METAL DETECTION VISUAL MONITORING

TECHNOLOGIES OF POTENTIAL

FT-IR ULTRASOUND NMR ELECTRICAL IMPEDANCE TERAHERTZ IMAGING HYPERSPECTRAL IMAGING RAMAN SPECTROSCOPY BIOSENSOR MICROWAVE

METAL

HAIR

NATURAL PLANT MATERIAL

WRONG PRODUCTS

RIPENESS

INSECTS

BONE

FAT, GRISTLE ETC

PLASTICS

GLASS (LIQUID)

POTENTIAL TO BE USED

GLASS (PARTICULATE)

CURRENTLY USED

DAMAGE TO FRUITS ETC.

Table 26. Technology versus sensing challenges and their abilities to meet them

CHALLENGES

Challenges

57

Each challenge - either suggested by the UKTI or identified subsequently - is analysed in the following way. Firstly, the challenge is put in context given its impact on UK recalls, and its potential health and safety implications. Secondly, the contaminant is analyzed for its physical, chemical and biological properties – this could aid in identifying previously unconsidered techniques for detection schemes. Thirdly, data from UK manufacturers is used to obtain a general image of how the challenges is currently being met and finally potential technologies are listed which may in the future result in new detection systems that can be employed. Comments and feedback from either manufacturer questionaires or captured from the workshop in London are incuded in quotation marks.

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1. The detection of glass fragments – in particulate food Background One of the most dangerous contaminations to find in food or drink is glass; it can cause internal bleeding and even be fatal. Glass fragments from food factories are occasionally found, for instance from such items as broken bottles from filling lines, broken fluorescent light tubes and broken glass viewing panels. Glass was the fourth most complained about foreign object in food in 2012.

Current situation The current main methods for detecting glass in particulate food and liquids with X-rays is that the density of these materials are often very similar, and as X-ray imaging operates on a density differentiation principle, will fail. Other methods used include visual inspection and sampling, however, the identification of small clear shards that can cause serious damage, is often non-trivial. Once contamination is confirmed, then microscopy examinations often take place. These examinations quantify features such as size, colour, curvature, surface scratches and deposits. This can be further followed up by X-ray microanalysis in the SEM. This non-destructive test gives a spectrum of the elements found in the sample to allow identification of the likely source of the contamination.

Manufacturers perspective X-ray imaging Lab Analytical 29%

29%

Sieving and Sampling Visual Inspection

21%

21%

Figure 16. Manufacturers current response to challenge

CHALLENGES

59

Contaminant Characteristics

PHYSICAL

Sharp; hard; reflect, refract and transmit light

CHEMICAL

Composed of SiO2

BIOLOGICAL

N/A

Potential for innovation

THz

Proof of principle experiments exist which show how THz imaging can highlight buried glass in chocolate and meat, Ref [48,49]. With increasing levels of pattern recognition – this could be extended to particulate food.

Figure 17. (left) THz image of glass in chocolate from Ref. 45 and (right) glass in meat from Ref. [46]

48. http://www.anteral.com/services/pharma_agri 49. Terahertz imaging spectroscopy for quality inspection in the food industry, Jansen, C. http://www,labint-online. com

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2. The detection of glass fragments – liquids in glass Background In glass bottled liquids fragments can arise from not only the source mentioned on the previous page, but also from the bottles themselves. Monitoring must therefore be performed over the entire production as glass contamination could occur at any point. Glass was the fourth most complained about foreign object in food in 2012.

Current situation The current main methods for detecting glass in particulate food and liquids with X-rays is that the density of these materials are often very similar, and as X-ray imaging operates on a density differentiation principle, will fail. Other methods used include visual inspection and sampling, however, the identification of small clear shards that can cause serious damage, is often non-trivial. Once contamination is confirmed, then microscopy examinations often take place. These examination quantify features such as size, colour, curvature, surface scratches and deposits. This can be further followed up by X-ray microanalysis in the SEM. This non destructive test gives a spectrum of the elements found in the sample to allow identification of the likely source of the contamination. Existing technologies for checking glass bottle integrity, such as ‘bottlevision’ are expensive

Manufacturers perspective X-ray imaging Optical sorting 29%

Sieving and Sampling

35%

Visual Inspection

18% 18%

Figure 18. Manufacturers current response to challenge

CHALLENGES

61

The detection of small glass fragments within bottled fluids is difficult Used extensively for soluble coffee granules in Glass Jars. Glass is serious customer complaint. There are still some ‘blind spots’ with X-Ray at certain points in the glass - would like to eliminate.

Contaminant Characteristics

PHYSICAL

Sharp; hard; reflect, refract and transmit light

CHEMICAL

Composed of SiO2

BIOLOGICAL

N/A

Potential for innovation

ULTRA

Proof of principle experiments exist which show ultrasonic measurements on canned and bottled goods. Restrictions exist in the geometry of the set-up and impedance matching requirements. But in principle extra reflections due to foreign bodies are measurable. Methods for mechanical sepration by spinning the liquid and bringing the contaminant to the surface The sound of glass being chipped could serve as a detectable signal

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3. The detection of plastic Background Plastics are an increasingly prevalent material of use in the food industry, both in manufacture and in packaging. Plastics were the second most complained about foreign object in food in 2012. The threats they pose however are not simply in choking and cutting but also in introducing a chemical and biological hazard to the consumer – depending on the source. Ultra-high molecular-weight polyethylene (UHMW PE) is probably the most widely used plastic in food processing facilities and also is used in conveyor guide rails. The detection of plastic is a big potential market for detection companies with many seeing it as one of their biggest challenges

Current situation Currently used methods for plastic detection are visual inspection, optical sorting and X-ray imaging. Identified problems with these techniques are that: Plastics do not possess the density contrast that metals do, thus making the detection of them with X-rays problematic Plastics are composed of carbon and oxygen, making the elemental makeup of the plastic very similar to organic food tissues The optically transparent nature of many plastics used in the food industry mean that visual inspection can often miss the presence of plastic. Solutions such as altering the properties of the plastic so that they may be detected by metal detection / X-ray sources have been trialed. Whilst seemingly advantageous in terms of ability to retrofit, they are unpopular for cost reasons, and for the difficulty of getting ‘new’ plastics into the industry. Additionally, altering process plastics would fail to detect contamination from random events.

Manufacturers perspective NIR 14%

Metal Detection 32%

13%

X-ray imaging Optical sorting

9%

Sieving and Sampling 14% 18%

Figure 19. Manufacturers current response to challenge

Visual Inspection

CHALLENGES

63

Filter medium + sieves are used to remove any particulates. Polycarbonate plastic pieces in moulded chocolate bars. Serious H&S issues. Huge expense. Detection generally involves retrospective investigation, embargoes etc.

Contaminant Characteristics

PHYSICAL

Largely varying, brittle to flexible, sharp to rounded, small to large, varying densities

CHEMICAL

mostly composed of complex hydrocarbon chains, but have a large range of chemical properties

BIOLOGICAL

N/A

Potential for innovation

METAL X-RAY IMAGE

IR

Ordinary plastics cannot be detected by metal detectors however, it has been suggested that magnetic additives to the plastics used in manufacture could assist in detection – thus utilising one piece of equipment. Similarly for X-ray detection, inclusion of a heavy element (such as barium) will cause the plastic to fluoresce under X-ray examination. … clearly however, this relies on the plastic contaminant being identified and replaced. Highlighted due to its innate suitability to organic materials and its subtle ability to differentiate foodstuffs from plastics due to the structure of the sample.

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4. The detection and sensing of fat and gristle Background Fat and gristle are very important to the meat industry as they determine yield. Nobody wants to buy a steak that is mostly inedible. Luckily, fat and meat tissue have different properties; moisture content, density, colour etc. and thus can be differentiated.

Current situation On farms, ultrasound measurements can give important information on fat and muscle depths, Ref. 50. In processing fat, gristle and meat content in food industries are currently determined by using the difference in absorption of fat and meat in NIR spectroscopy, NIR relies on the difference in absorption of different organic compounds and can give information on key qualities such as texture, juiciness and flavour. ELISA is used for quantitative analysis of fat content but is an off-line destructive method. For often, simple visual inspections of the meat are used to determine fat and muscle content. There appears to be a large number of approaches to sensing fat, gristle and cartilage. Most of these techniques are involve moisture detection – IR, microwave etc.

Manufacturers perspective NIR ELISA 30%

Visual Inspection 40%

30%

Figure 20. Manufacturers current response to challenge

Contaminant Characteristics A comprehensive list of physical, chemical and biological characteristics of muscle, fat and gristle etc are presented in Ref. [51]

50. Improving sheep carcass quality using CT scanning 51. Handbook of Meat, Poultry and Seafood Quality, Leo M. L. Nollet, Wiley (2012)

CHALLENGES

65

PHYSICAL

Difference in colour, texture, spectral response and water holding capacity to surrounding tissue,

CHEMICAL

Generally insoluble in water, composed of hydrocarbon chains

BIOLOGICAL

N/A

Potential for innovation

NMR

Academic work using NMR technique has been pioneered for 3D maps of fat distribution, using an identical set up as that for medical imaging, Refs [52 and 53]. Mainly for analytical laboratory tests.

HYP

Commercial hyperspectral imaging is currently limited by the somewhat small sample areas that are illuminated – although breakthroughs have been made in whole carcass scanning, Ref. [54]

OPT SORT

Advanced signal processing and machine vision, which can optically and automatically detect fat by edge detection, would be a applicable method.

X-RAY IMAGE

Selection of meat sheep on CT measurements could increase genetic progress by up to 50 % per annum compared to selection on ultrasonic measurement [50]

ULTRA

There is ongoing work in the non-contact ultrasound area, via high power ultrasound or photoacoustic imaging. However, the performance of the detection may not improve significantly on existing equipment, although ultrasound could potentially have uses in whole joints.

52. A. Spyros ad P. Dais, NMR Spectroscopy in Food Analysis, Royal Society of Chemistry (2013) 53. Using Nuclear Magnetic Resonance to Test Fat Content in Foods, Case Study 54. Prediction of Meat Quality: application of hyperspectral imaging and Raman spectroscopy, Moss et al ()

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Figure 21. (left) NMR measurements of different cuts of pork (adapted from Ref. 49) (right) hyperspectral image of meat with colours corresponding to different fatty acids from Ref. 51

CHALLENGES

67

5. The detection of bone in meat and poultry products and in fish Background The density difference between meat and bone is small. Rate of “false positives” can be high – approximately 50 % in some cases, Ref [55]. The presence of bones in food constitutes the fifth highest cause of complaint in the UK in 2012. It may also be worth considering the fact that bone in fish and meat is an ‘accepted risk’ by the consumer, in a fillet of fish one almost expects to find pin bones in fish and would not naturally consider complaining – this does not lower the risks associated with them. It may be appropriate to assume the number of incidents associated with fish bones is in-fact higher than the statistics suggest.

Current situation The detection technologies for meat and bone for fish meat and poultry products has largely remained the same for decades, Ref [56]. Automated X-ray systems remain favourites for on-line detection; these systems are reasonable inexpensive, low maintenance and highly penetrating. One disadvantage however, is that there are important health and safety implications to adding an ionising radiation source to a production line. Visual inspection suffers from not being able to see inside the meat and so must be used in conjunction with X-ray techniques. However, as is discussed in the X-ray imaging section – pin bones, cartilage and non calcified bone tissue is not picked up by X-ray mainly due to their small size and similar density to surrounding tissue.

Manufacturers perspective Optical Sorting X-ray imaging 27%

27%

Visual Inspection

46%

Figure 22. Manufacturers current response to challenge

55. Existing Automated Foreign Body-Detection Systems in the Food Industry 56. Private communication with Campden BRI (2013)

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Contaminant Characteristics PHYSICAL Various sizes, sharp,

CHEMICAL BIOLOGICAL

Mainly comprised of calcium phosphate mineral and collagen N/A

Potential for innovation

ULTRA

Ultrasonic measurements can be used when there is a large impedance mismatch in a sample, the implementation of this technique in are and more in-homogenous substances needs work, Ref [57]

X-RAY IMAGE

If the sensitivity, accuracy and false positives can be safely negated by technology advances – it may remain a key technology. New work in other X-ray techniques aside from conventional X-ray transmission radiography such as X-ray dark-field imaging with a grating interferometer could advance the technique, Ref [58] Energy selective X-ray systems (spectroscopy) seem to be the most sensible approach to do this. This method would allow the different tissues to be identified and has the advantage of being simple and cheap to retrofit onto existing production lines. Imaging in the IR regions could work for larger bone fragments, but would require the product to be flattened out – this may be appropriate for minced meat, but not for whole fillets.

57. Ultrasound detection and identification of foreign bodies in food products, Food Control, 12, 1 (2001) 58. X-ray dark-field imaging for detection of foreign bodies in food, Food Control, 2, 531 (2013)

CHALLENGES

69

6. The detection of insects in fruits and vegetables Background Most companies regard complaints about insects as one of the most important. One of the main reasons is the difficulty of detecting and removing insects and pests (Spiders, bottom-feeders, slugs, snails.) on a production line, particularly in fresh produce. Pests were the second most complained about foreign object in food in 2012.

Current situation The presence of insects can be inferred directly or indirectly with associated signs such as the occurrence of molds and increased mycotoxin levels in food. There are several used detection methods application for commodity samples, these are shown on the right hand side. Visual inspection dominates the detection methodology, it works well for identifying large infestations and the signs of insect presence, but like all visual inspection requiring a human worker it leads to variable results and high resource usage. Washing and sieving were also answers given as methods for detection / separating out insects in vegetables and fruit.

Manufacturers perspective Wash Optical sorting

19%

Sieving and Sampling 37%

Visual Inspection 25%

19%

Figure 23. Manufacturers current response to challenge

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Contaminant Characteristics

PHYSICAL

Visually different to the food they are in

CHEMICAL

N/A

BIOLOGICAL

Biological in nature, the presence of insects will leave organic signatures in the food.

Potential for innovation

ULTRA

Ultrasound systems can detect impedance mismatches which can result from insect infestation.

NMR

Has been done for many years on fruit and Ref 37 lists many examples. Its slow measurement time and high resource cost still make the methods unsuitable for online detection. See Figure 24 for examples.

µwave

THz HYP

Microwave and THz methods can inspect food for high density and low density foreign bodies – including insects Refs [59 and 60]

Just as hyperspectral imaging could determine damage to the surface of an apple, it could also locate the presence of insects.

59. Private communication with Campden BRI (2013) 60. Detection of foreign bodies in foods using continuous wave terahertz imaging, J Food Prot. 75, 179 (2012

CHALLENGES

71

Sound as a means of detecing infestation was mentioned in the workshop – wither through the use of simple mirophones, or listening in the ultrasonic range. Electronic noses or other small mass spectrometry-like solutions were porposed to detect insects by the gasses (smell) they give off. Similar to the breath analysis techniques for human health monitoring.

Figure 24. NMR images of various fruit Ref. 61

61. http://wellcomeimages.org/

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7. The quantification of ripeness in fruit Background Catching fruit when is about to go bad would cut down on the 10 % of fruit and vegetables that go bad on store shelves every year, Ref [62]. There are a few indicators in for when fruit is at its ripest, these are a balance of sugar content and acidity. Current situation There are many chemical tests that can determine the levels of the numerous indicators of matureness / ripeness. Currently used methods for determining the ripeness of fruit include: •

Brix determination: Brix (oBx) is the sugar content of an aqueous solution; one degree Brix is 1 gram of sucrose in 100 grams of solution. Ways of measuring Brix include refractometry, NIR and others.

•

Visual inspection involves production workers monitoring the colour, shape, size etc. to qualitatively determine its ripening stage.

•

The firmness of fruit is often the what is tested by the customer at the end of the process for optimum ripeness. Industrial processes do exist for this on the production line – such as a pentrometer. Acoustic tapping [63], air puff testing.

Manufacturers perspective Pressure Optical sorting

23% 31%

BRIX Visual Inspection

23% 23%

Figure 25. Manufacturers current response to challenge

62. The World Fresh Fruit Market, US Dept. of Ag.(2004) 63. http://www3.imperial.ac.uk/nde/researchthemes/inspection/ultrasound/

CHALLENGES

73

Contaminant Characteristics

PHYSICAL

fruit firmness, colour

CHEMICAL

pH level, sugar content

BIOLOGICAL

N/A

Potential for innovation

ULTRA

Non-destructive acoustic techniques for the measuring the firmness of fruits may see ultrasound being commercially used.

BIO SENSOR

Stickers currently exist for certain fruit that measure the aroma of fruit as it ripens – the stickers change colour to indicate its level of ripeness, Ref [64].

µwave

Microwave detection Ref [65] uses water content an indicator of ripeness (well distinguished by microwaves) to determine ripeness. The case of strawberries is shown in Figure 26 (left)

THz

Similar to microwave techniques, Figure 26 (right) shows a leaf that has been cut and interrogated by THz radiation for water content.

Any method which is sensitive to moisture content; microwave, dielectric spectroscopy, THz, MIR, NMR and NIR. The combination of detection evidence, ability for packages to modify atmospheres to slow / speed up ripeness process and the use of prediction algorithms would go a long way to ensuring fruit and vegeatbles arrive to the consumer at their peak condition.

64. http://www.ripesense.com/ripesense_background.html 65. Robot Learns to Pick the Sweetest, Ripest Strawberries, http://www.wired.com/gadgetlab/2012/08/st_strawberry_robot/ (2012)

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Figure 26. (a) microwave reflectance image from Ref. 62 (b) THz image of leaf from Ref. 61

and (c) HSI image of a melon in various stages of ripeness [66]

66. Visualisation of sugar distribution of melons by hyperspectral technique. In: Sun, Da-Wen (ed), Hyperspectral Imaging for Food Quality Analysis and Control, Chapter 11, pp. 349-368, Academic Press / Elsevier, San Diego, California, USA.

CHALLENGES

75

8. The detection of damage and mould in fruits and vegetables Background Until about 50 years ago, the spoilage of food by micro-fungi was regarded as a quality issue rather than a food safety concern. Fungal spoilage of food remains a serious problem, one that has been estimated to account for between 5 % and 10 % of all losses in global food production. Damage in fruits and vegetables are also a serious problem, these can arise through natural causes before the prime producer but also through improper handling. Unattractive and damaged fruit and vegetables cost the food industry money in waste and affect consumer confidence.

Current situation For mould detection, colony count methods require 5 – 7 days to achieve a result. The interpretation of conventional colony counts can be difficult requiring considerable staff input. The respondents to this report highlight the main methods for damage and mold detection are through visual inspection of the products and random sampling. It should be noted however that for certain fruit and vegetables, this rotting can occur inside where visual inspection can miss.

Manufacturers perspective Optical sorting Sieving and Sampling 25%

Visual Inspection 50%

25%

Figure 27. Manufacturers current response to challenge

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Contaminant Characteristics

PHYSICAL

Damage and mould can affect texture, smell, water content, shape changes

CHEMICAL

pH change, sugar content change

BIOLOGICAL

EI µwave

HYP

Growth of mould

Potential for innovation In Ref [67], electrical impedance measurements were made on an apple before and after bruising. Distinct resistance changes are observable

Due to the relatively large penetration of microwaves the state of vegetable interiors can be investigated, such as rot inside potatoes, Ref [68]. Proof of principle work on hyperspectral imaging for bruise detection in apples, Ref [69]. The reflectance spectrum is characterised by a spectrum change, Figure 28

Key indicators for damage and mould were identified at the workshop and technologist were encouraged to come up with solutions from these: •

Firmness

•

Chemical / VOCs / Pathogen release

•

Discolouration and visual signatures of rot

•

Many of the indicators for ripeness could be used as a prediction tool for the likeliness of rot.

67. Apple Bruise Detection by Electrical Impedance Measurement, HortScience, 35(1), 104 (2000) 68. Private communication with the NPL (2013) 69. Detection of Bruises on Apples Using Near-Infrared Hyperspectral Imaging, Lu, R., American Society of Agricultural Engineers, 46 (2003)

CHALLENGES

77

Figure 28. Hyperspectral image of apple surface, adapted from Ref 66

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9. The identification of the wrong product in a package Background Trust in the UK food industry was damaged by the 2012 horsemeat scandal where traceability of ingredients was not properly observed. Food adulteration can have huge consequences; the addition of elements that are not included in the ingredient list can have very serious consequences for allergy sufferers.

Current situation Ingredient traceability is hugely important – currently to ensure that things being produced are what they are supposed to be, assurances from suppliers are relied upon. To prevent large scale recalls and industry confidence damage, a more rigorous approach may be required. A highly integrated and centralised produce chain where produce elements can be traced back to prime producer through barcoded database approaches is currently a good method for miniminisng mistakes. However, techniques for actively checking what is going into a product rely heavily of visual inspection. Miscoding products was suggested as one of the largest sources of failure at the end of the packaging line. Wrong shelf life date is a common issue (e.g. 2051 in place of 2015). A lack of universal standards in machine languages was largely attributed for this. Short run products (which are commonplace in the chilled food industry) are most susceptible to this control failure.

CHALLENGES

79

Manufacturers perspective Traceability and correct packaging is technology area ripe for the picking - Ref [70] Supplier assurance systems to ensure that ingredient suppliers are controlling their process effectively Bar Code Optical sorting

20% 33%

Sieving and Sampling Visual Inspection

27% 20%

Figure 29. Manufacturers current response to challenge

Potential for innovation

THz

Due to the ability for THz radiation to penetrate plastic and most packaging, contents can be interrogated to ensure the correct things have been packed.

RAMAN

The non-contact technique of Raman spectroscopy can cheaply and quickly fingerprint constituents of a product. With references, unexpected adulterations can be removed.

Attendees of the workshop were aware of technologies that could check the packaging (but not the product) via bar-code readers etc. but the groups were not informed about industrial adoption of this technology. There were suggestions that technologies in the NIR or THz area would be able penetrate the container and product (although not metallised packaging) and could identify shape using shape recognition software. Additionally, these techniques have the ability to gather compositional information (protein, fat etc.) however detailed information from the short wavelength the NIR region is difficult.

70. Private communication with the Cambden BRI (2013)

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10. The detection of “natural plant materials” Background Natural products of plant origin can often find their way into food production lines. Extraneous vegetable matter (EVM) are frequently found to be the case of contaminants in vegetables such as beans or fruits. Woody materials from the centre of a carrot or parsnip roots or cabbage stems. EVM is often of the same composition as the food stuff of interest, as such analysis of the material for composition will not offer a huge amount on benefit. If concern is raised about the origin of some unknown EVM contaminant, the type of material can be identified under microscope for cell structure - this however, is a resource intensive, off-line method used once a problem has already been identified.

Current situation Respondents to this report highlight that the methods currently used are visual inspect and sieving of the materials. Sieving and separation can only really be applied at a certain type of foodstuff, whilst visual inspection suffers from varying quality results and high resource use. Another response was the use of optical sorting methods which use machine vision and pattern recognition to identify martials that do not fit the norm.

Manufacturers perspective NIR 14%

Mass Spectrometry 29%

9%

Optical sorting Sieving and Sampling Visual Inspection

24% 24%

Figure 30. Manufacturers current response to challenge

CHALLENGES

81

Contaminant Characteristics

PHYSICAL

Texture, density difference to the surrounding material

CHEMICAL

N/A

BIOLOGICAL

N/A

Potential for innovation

??

The technology is required to distinguish natural products which are physically and chemically similar to their surrounding material.

Despite this, some suggestions can be made: improvements to visual inspection systems would seem a logical solution; benefits may arise from augmenting optical sorting methods with techniques such as: •

Vision systems

•

Particle sizing systems

•

Hyperspectral imaging

•

Reflectometry

•

Capacitance tomography

•

Dielectric spectroscopy

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11. Hair and fibre contamination Background Finding hair in food can be one of the more upsetting incidents for a consumer. The source of the hair is often from human intervention – and while these incidents are high on the HAACP agenda and various methods of prevention are in existence (hair nets, ban on beards, gloves etc.) the discovery of hair rarely prompts a recall due to the randomness of the event The presence of rodent hair may be an indicator of rodent infestation at some point in the food chain. Sources of artificial fibres can be bristles from brushes, twine from factory sacks, woolen fibres from clothing. The exact identification of these can be made using FT-IR, Ref. [71]

Current situation Hair presents a huge challenge for X-ray inspection technology, its low density and very small (10 – 200 µm) dimensions make it always impossible to detect in small quantities. Simply put, the prevention of the hair ending up in the process will be easier than detecting it as a contaminant.

Contaminant Characteristics

PHYSICAL

Small 10 – 200 µm, high tensile strength

CHEMICAL

Mostly composed of keratin, high concentration of cysteine, can carry distinctive chemicals from product

BIOLOGICAL

N/A

Potential for innovation Technologies are suggested which are not sensing solutions used to detect the hair itself, but instead non-compliance with procedure (analogous to hand washing solutions in healthcare). For example, an optical sensing system to monitor whether hairnets are being sed correctly could be used to flag an alarm of non-compliance.

71. Foreign body complaints in the food ad drink industry, Newfood Magazine, Issue 2, Page 9 (2013)

CHALLENGES

83

12. The detection of metal of any sort of food product Background Despite the fact that metal detection is one of the most common and oldest forms of foreign object detection – it remains a large cause for concern in the food industry. Indeed, from 2006 – 2012 physical contamination from metal has increased its proportional share largely whilst the total number of incidents has not changed significantly. The reason for this increase of the 6 year period is unclear. European Frameworks exist to limit the amount of metals in food and drink in the EU, heavy metals such as cadmium, lead, arsenic etc. are present in the environment and if ingested can build up and cause serious health problems in living organism. Metals in food industry process are intentionally used for their hardness, often found contaminants are large objects, nuts from machinery, shot from shotgun, metal wool, sieve components etc. These large objects have the ability to cause a choking hazard, damage the inside of an organism or break teeth.

Current situation Metal detection systems are ubiquitous in food manufacturing plants which must make the continuing hazard posed by incidents extremely frustrating for manufacturers. Energy dispersive X-ray analysis is a quick and non destructive method that can be used on metals, often performed in conjunction with microscopy techniques - this combination can reveal evidence on the course of contamination once a contamination has been identified but is currently not an in-line technique. Technologies need to be adaptable for new materials introduced to supply lines, titanium, stainless steels, almunium and other lightweight metals.

Contaminant Characteristics

PHYSICAL

Sharp, electrically conductive, can be magnetic

CHEMICAL

Wide range of chemical properties

BIOLOGICAL

N/A

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Potential for innovation A seemingly satisfactory solution might be in improving the performance / expanding the capabilities of current technologies. For example, energy selectivity X-ray detectors could be retrofitted onto existing lines for the identification of metals. Methods for monitoring dielectric properties of contaminated foods were discussed as a possible solution, given that metal would have a noticeably different signature to surrounding material.

CHALLENGES

Conclusions

85

The key challenges identified are extremely varied in their requirements – no one technology will solve all of these challenges. A large number of the techniques available have the potential to be able to ‘fingerprint’ a contaminant. These are either chemical techniques (mainly off-line) but also spectroscopic techniques based on the scattering and absorption of different parts of the electromagnetic spectrum. Communication with UK manufacturers highlight the needs of the commercial food manufacturing sector in these areas. The manufacturing sector requires: Seeking in-line methods, which reduce number and frequency of tests. We are always very keen to use non-destructive techniques so we can reduce waste levels generated during testing Identified areas of concern are those where detection methods are based on either: Visual inspection or assurance systems that ingredient suppliers are controlling theirprocess effectively. There is also an ongoing trend away from traditional X-ray imaging due to health and safety concerns and the success rate of X-ray machines. Key identified challenges where either the complaints remain too high or where innovative technologies couldn’t be adequately found are: •

Glass in bottled liquids

•

Metal in food and drink

•

Plastics in all food

•

Pin bones, cartilage and non-calcified bone tissue.

Various technology areas have been looked at for this report with communication with consultants and national laboratories. These technology areas can be split into two categories; areas which have been developed but are not applied in this sector and areas which are at a lower readiness level.

Non-commercial / emergent technologies: THz: longer wavelengths than traditional light source allow the depth of penetration to be increased. This may have the advantage of looking into sealed packages, and water concentration monitoring for a variety of purposes. Overly expensive and low technology readiness equipment mean that the roll out of these devices is a way off. Hyperspectral: whilst there do exist some commercial technologies, the wide scale roll out of these has not yet been achieved. Technology does however exist and is becoming more available on the commercial market. The wide range of contaminants able to be sensed makes this an attractive technology.

Ready in linked sectors Microwave: The technologies exist for detection and production of microwave radiation, and indeed much research is currently being done

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on the uses of this in the food sector X-ray techniques: the food sector has benefited greatly from the use of X-rays, although going out of favour, advances in sensitivity and tomographic approaches continue to make X-ray imaging and attractive option Biosensors: becoming highly prevalent in the medical and environmental markets, it is assumed that if they can be made to fit the industry needs, they will make good progress in the food market also – although their limitations to off-line techniques make the implementation of these difficult. Raman: Raman is making important inroads into many sectors, healthcare, environmental monitoring. Whether it can fit into the food market by covering the important challenges detailed remains to be seen [72]. Ultrasound: well known in NDE circles the application of ultrasound to the food and drink sector is not well developed, key to its exploitation is furthering is ease of application and quantifying the limits of detection it can offer. Linked sectors: There are a number of linked sectors whose input could increase the rate of pull through for many of these challenges: 1. Healthcare: advanced biosensors are being developed for disease detection which could be linked 2. Defence and Security: detecting things that should not be there is a goal of defence and security. Many technologies used there are applicable in the foreign body sensing world 3. Material science: many limiting factors in the spectroscopy methods are closely related to the high price of source and detector technology. For example fast and accurate multispectral CCDs are not cheap, disruptive advances in this area would help

Barriers to innovation There are however inhibiting factors to innovation in this sector; food industry representatives are often looking for better versions of what already exists. Engagement events are key to exposing the up and coming technologies to food industry representatives to technology areas outside of their own areas of expertise and sector. Although a huge industry, the food industry can be very conservative in the adoption of new technologies and it can require much higher rates of return on capital investment than can be delivered, therefore the food industry seeks low- cost solutions that can justify the effort. The idea that product recalls can be reduced or prevented by better training, procedures etc. is a far more appealing alternative to large R&D investments. 72. Note on spectroscopy: whilst the detection of what is inside our food is obviously an important goal for manufacturers, there may be concern from manufacturers about the level to which technology is able to do this. The ability to reverse engineer expensive and complex food and drink will likely not be well received by the manufacturing community.

APPENDIX 1

Appendix 1. UK capabilities in highlighted areas

87

The UK capability in relevant areas has been assess on the basis of conclusions drawn from Appendix 3: RCUK Grant Analysis. The grants awarded with keywords as any of the identified technology areas are analysed for their Technology Readiness Level (TRL), the activity in the Research Councils and the relevance the technology has to the food sensing sector. See Table 27 for results. Identified technologies areas with a high relevance to food sensing; ultrasonics, hyperspectral and

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Table 27. RCUK Technology Capability Analysis

TECHNOLOGY CATEGORY

KEY INSIGHTS

REPORTED ACTIVITY LEVEL

RELEVANCE OF TECHNOLOGY CATEGORY FOR SECTOR

• Large spread of addressed sectors TERAHERTZ

• TSB money is funded heavily to one company • Primarily funded at the EPSRC level, where sources and detectors are the focus

HIGH

MED

HIGH

HIGH

LOW

HIGH

MED

HIGH

MED

MED

LOW

MED

HIGH

LOW

• Many TSB grants in the food sector here • Unsurprising amount of grants from MRC ULTRASONIC

• Focuses on imaging applications • Wide range of disciplines using technique • Developments in medicine are to rival traditional imaging, drug delivery • HVM applications, defects, joints etc.

HYPERSPECTRAL

INFRARED TECHNIQUES

• A large number of these proposals come from one company, M-Squared Lasers • Funding majorly into Earth Observation and space missions. • Number of biological projects funded • Space technologies funded in the IR areas • Space and EO applications

RAMAN

• TSB funded only a few companies • Medical and biological charactisation • STFC funded projects for niche product development for UK Mars missions

CAPACITANCE / IMPEDANCE TOMOGRAPHY

• Slim pickings • Interesting spread of applications • Big funding for biosensor networks for sports

BIOSENSORS

• Large programmes • Well covered across all RCUK • Some for the food chain • Strong funding for medical

APPENDIX 1

89

Each of the selected technology areas identified in the report and workshop discussions have been analysed in terms of the UK Research Councils grant funding aimed in those areas [73]. The relevant projects are extracted, an estimated technology maturity level (TML) of the project assigned to them and graphed.

TML 1 PROBLEM IDENTIFIED

TML 2 PRINCIPLE UNDERSTOOD

TML 3 PROOF OF CONCEPT

TML 4 REALISTIC DEMONSTRATION

TML 5 SYSTEM PROTOTYPE

TML 6 NICHE PRODUCTION

TML 7 MASS PRODUCTION

Problem identified – academic, basic principles being questioned

Principles understood – academic exploration, understand associated physics early level experiments to validate theories. Development of underlying components

Proof of Concept – academic, can the device function as required

Realistic Demonstration at commercial level, can the device function in a realistic scenario

System Prototype, commercialise. Does the product exist as a assembled, integrated prototype

Niche Production, is the project going into niche production

Mass Production, is the product going into mass production

Care was taken to identify projects where only technology advancement in the technology area was the purpose of the project and from the public description (if available). The TML was estimated using the following criteria:

The resulting graphs give an indication as to would stage the UK research in that technology area is at, and what research councils are currently funding it. Key insights from the project descriptions are attempted to add to the graphs and a diagram of keywords is presented at the end of each technology section [74]. The geographical spread of academic groups involvedin the RCUK grants and any industrial partners are included to highlight areas of excellence.

73. Data extracted from http://gtr.rcuk.ac.uk (only projects post 2006 are included) 74. Images formed using http://www.wordle.net

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TSB

Technology Strategy Board

STFC

Science & Technology Facilities Council

NERC

Natural Environment Research Council

MRC

Medical Research Council

ESRC

Economic and Social Research Council

EPSRC

Engineering and Physical Sciences Research Council

BBSRC

Guide to the Research Councils

Biotechnology and Biological Sciences Research Council

AHRC

90

Arts and Humanities Research Council

APPENDIX 1

91

Terahertz Terahertz technology is an emergent technology, as such, all instances of THz radiation being used in a research project is included in this survey. It is concluded in Ref. [75] that there is a full supply-chain with system, subsystem, component and material suppliers in the UK for THz radiation - Teraview Ltd is one of the world’s leading suppliers of commercial equipment for close-in active imaging and spectroscopy at THz frequencies. Thruvision (Oxford) manufacture security screening products which detect passive Terahertz radiation from the surroundings. Other UK companies involved in THz are M- Squared Lasers who manufacture THz laser sources based on ultrafast pulse lasers, QMC Instruments Ltd, which manufactures instrumentation and Teratech Components Ltd (THz electronics). e2v technologies are suppliers of low-THz Gunn diode components and mixer/amplifier subsystems, and the University of Manchester are commercial suppliers of GaAs-based epiwafers through a subsidiary company. There is also a significant tail of specialised microwave sensing groups like Navtech Ltd which integrate systems for defence and security applications at lower frequencies, but are potential entrants at higher frequencies. Academic groups like those at Cambridge, St Andrews, Leeds, RAL, Essex, UCL, QMC, Cardiff, and Manchester cover the full range of “optical sources”, “solid-state microwave-sources” and detectors for THz, with system integration, whilst the STFC facilities at Daresbury, and associated academic groups provide a full supply chain for “vacuum electronic tube” sources for THz at higher powers.

Key words “THz” or “Terahertz” Statistics AHRC

BBSRC

EPSRC

ESRC

MRC

NERC

TSB

STFC

1

0

55

0

0

0

4

4

Number of funded projects in this area since 2006

64

Number of live projects

31

75. Roadmap: UK III-V Community Engagement with Industry, ESP-KTN (2012)

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TML Analysis 35 Total 30 TSB 25 STFC 20 NERC 15 MRC

Terhertz

Diodes resonant

electron painting

Systems

Devices

Substrates

exploiting

T-Ray Advanced

surgery

Fibre-Based Quantum Novel

brightness

EMISSION

Planar

far

beams

Fast Thermal

controlling Temperature

relativistic

Coherent

Imaging

generation AMPLIFIERS Cascade

pseudospark-sourced innovative processes

Tomography Electroniic probe InP SEMICONDUCTOR

multi

10 ESRC 5 EPSRC 0

TML 1

TML 2

TML 3

TML 4

TML 5

TML 6

TML 7 BBSRC

AHRC

Key Insights • Large spread of addressed sectors • TSB money is funded heavily to one company

• Primarily funded at the EPSRC level, where sources and detectors are the focus

Total RCUK Funding: £ 33,177,105

APPENDIX 1

93

Map of RCUK academic (yellow) and industrial (red) grant receivers. The locations are approximate and the size of the circles represent the number of grants at that institution

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Hyperspectral There are various UK companies working at various points in the supply chain for HSI equipment; a notable company is Gilden Photonics which in partnership with the University of Strathclyde, Hamamatsu and Specim run the Hyperspectral Imaging Centre. There are strong groups of research in HSI in the UK with applications covering many sectors such as food and agriculture, homeland security and medicine. Universities such as Strathclyde, Glasgow, Cranfield, Manchester, Birmingham and Leicesterare active in fundamental technology research (detection and signal processing)

Key words “Hyperspectral” , “HSI” or “multispectral” Statistics AHRC

BBSRC

EPSRC

ESRC

MRC

NERC

TSB

STFC

1

0

1

0

0

1

5

7

Number of funded projects in this area since 2006

16

Number of live projects

6

APPENDIX 1

95

TML Analysis 6 Total 5

Camera

WAVE system oil

optical suppression Offshore

remote

instrument

lifetime

Active

oscillator sensing Long

techniques

Laser-based

wastes

applications

hyperspectral measurement

biogenic

SKYDOME

TSB

4

STFC

3

NERC

2

MRC

ESRC

1

EPSRC 0

TML 1

TML 2

TML 3

TML 4

TML 5

TML 6

TML 7 BBSRC

Figure 31. TML for HSI RCUK projects

AHRC

Key Insights • A large number of these proposals come from one company, M-Squared Lasers • Funding majorly into Earth Observation and space missions.

Total RCUK Funding: £2,709,295

remote

fluorescence USING disease

development

examination archaeological

optical VIS-IR Harmonic Active portable

gas

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Map of RCUK academic (yellow) and industrial (red) grant receivers. The locations are approximate and the size of the circles represent the number of grants at that institution

APPENDIX 1

97

Capacitance and electrical impedance tomography Key words “capacitance tomography”, “capacitance imaging” ,“impedance imaging” and “impedance tomography” Statistics AHRC

BBSRC

EPSRC

ESRC

MRC

NERC

TSB

STFC

0

0

3

0

1

1

0

1

Number of funded projects in this area since 2006

6

Number of live projects

3

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TML Analysis 4.0 Total 3.5 TSB 3.0 STFC

2.5 2.0

NERC

1.5

RIVER

sensor viability

Ultra-fast Early Magnetic

plc measurement feedback electrical intervention thrombolytic

pharmaceutical

imagine

morphology EIT

particulate

Resonance

tomography

measurement

impedance

GAS-SOLID

control

Complementary stroke viability

fluidised

complex

distribution

Bath Array Magnetic industrial acute

granule

MRC

1.0 ESRC 0.5 EPSRC 0.0

TML 1

TML 2

TML 3

TML 4

TML 5

TML 6

TML 7 BBSRC

Key Insights

AHRC

• Slim pickings • Interesting spread of applications

Total RCUK Funding: £1,546,203

APPENDIX 1

99

Map of RCUK academic (yellow) and industrial (red) grant receivers. The locations are approximate and the size of the circles represent the number of grants at that institution

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Biosensors For a detailed analysis of the UK capabilities in biosensing refer to Ref. [38]. The UK has a strong commercial biosensors community – however it is highly focused in medicine and healthcare markets, and so is limited in its responsiveness to other opportunities. Existing institutions, for examples the CPI / Medtech KTN / Biosensors KTN and existing industry/academic collaborations such as the Cambridge IKC etc. can facilitate the pull- through. Nationally funded programmes by groups like the Environmental Agency (EA), NERC and MOD also provide some pull-though into demonstration for specific technologies in niche applications. Both MOD (via the Centre for Defence Enterprise) and NERC are active in seeking to build commercial impact from this research. The UK boasts a strong academic capability in biosensing research with worldclass research instutions such as at the Universities of Exeter, Cardiff, Bristol, Reading, Oxford, London, Southampton, Cambridge, Cranfield, Manchester, Durham, Newcastle and Belfast.

Key words “biosensor” Statistics AHRC

BBSRC

EPSRC

ESRC

MRC

NERC

TSB

STFC

0

11

12

0

1

2

0

8

Number of funded projects in this area since 2006

34

Number of live projects

11

APPENDIX 1

101

TML Analysis 20 Total

TSB 15 STFC

10

DRUGS

Active

circuits

MRC

WHOLE-CELL

5

biosensing

ESRC

synthetic

plc micro-chemostat MRSA detection piezoelectric warning

EPSRC 0

pharmaceutical

spectrum

engineering GENE

explosives

NERC

chemical

biosensor

ultra-sensitivity

waveguide

TML 2

TML 3

TML 4

TML 5

TML 6

TML 7 BBSRC

AHRC

Key Insights • Big funding for biosensor networks for sports • Large programmes • Well covered across all RCUK • Some for the food chain

Phage self-regenerating MATERIAL

TML 1

Total RCUK Funding: £ 14,467,904

Film

Polymer

development

cell

monitoring

Bulk Acoustic rapid synthetic broad

advanced

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Map of RCUK academic (yellow) and industrial (red) grant receivers. The locations are approximate and the size of the circles represent the number of grants at that institution

APPENDIX 1

103

Ultrasonic According to the Cohort Study by the ESP Sensors and Instrumentation group, Ref [76] – there are 126 UK groups developing or distributing ultrasonic sensors, sub-systems or instrumentation with large interests in sectors such as aerospace and defence, automotive, building, energy and security- but very little in the agriculture sector (where food would lie in the classification system of the study). Some companies such as Mainstream Measurements, Hach Lange provide ultrasonic solutions for environmental monitoring for pipes which could be applicable to food technologies. The UK hosts many groups working in the field of NDE using ultrasonics, Strathclyde, Warwick, Leeds and Bristol. The research activities are varied due to the large cross-applicability of the technique. The activities include research into materials stress and damage for construction, NDE for pipes, transport infrastructure etc. Ultrasonics is a well-established technique in NDE, for the purposes of this assessment, projects were analysed which: Applied the technique in unknown configurations Used in conjunction with other techniques to extract new information Develop novel process design, sensor design. Projects are NOT included which use the technique as a tool in standard configurations.

Key words “Ultrasound” or “ultrasonic” Statistics Number of funded projects in this area since 2006

135

Number of live projects

42

AHRC

BBSRC

EPSRC

ESRC

MRC

NERC

TSB

STFC

0

12

81

2

8

0

11

0

76. Cohort study of the Commercial Sensors and Instrumentation community of the UK, to be published 2014. ESP KTN

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TML Analysis 60 Total 50

microbubbles

NDE

development

Arrays Non-Detructive techniques

gene sonotweezers imaging New Structures

lasers

biosensor

Real using

NON-CONTACT

Automated rye-grass

development

TIME monitoring

gun Sound joints surface components

intensity

30

NERC

20

MRC

ESRC

EPSRC TML 1

TML 2

TML 3

TML 4

TML 5

TML 6

TML 7 BBSRC

AHRC

Key Insights • Many TSB grants in the food sector here • Unsurprising amount of grants from MRC • Focuses on imaging applications

characterisation •

nonlinear

STFC

0

Tomography

material application CANCER

40

10

monitoring

processes

TSB

Wide range of disciplines using technique

• Developments in medicine are to rival traditional imaging, drug delivery • HVM applications, defects, joints etc.

Total RCUK Funding: £58,073,043

APPENDIX 1

105

Map of RCUK academic (yellow) and industrial (red) grant receivers. The locations are approximate and the size of the circles represent the number of grants at that institution

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Infra-red Techniques Infrared techniques have been used for many years in many technology, for the purposes of this assessment, projects were analysed which: Applied the technique in unknown configurations Used in conjunction with other techniques to extract new information Develop novel process design, sensor design. Projects are NOT included which use the technique as a tool in standard configurations.

Key words “FTIR” or “IR” or “NIR” Statistics AHRC

BBSRC

EPSRC

ESRC

MRC

NERC

TSB

STFC

1

0

10

0

0

1

1

7

Number of funded projects in this area since 2006

20

Number of live projects

8

APPENDIX 1

107

TML Analysis 8 Total 7 TSB 6 STFC

5 4

NERC

3

spectroscopic

EChO

2 ESRC

antibodies

Miniature Optical Telescopes

Leak Nanoparticles FTIR imagingfocal-plane

MRC

1 EPSRC 0

Astrophysics

TML 1

TML 2

TML 3

TML 4

TML 5

TML 6

BBSRC

Sensors

Detector

Spectrometer POLYMER

Applied

Transform

Enzyme

TML 7

AHRC

Key Insights • Number of biological projects funded • Space technologies funded in the IR areas

simultaneous

Technology

Total RCUK Funding: £7,054,841

New therapeutic

low cost

camera

SUPPORT heritage

brain Gas Fourier Petrochemical skin

free-space

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Map of RCUK academic (yellow) and industrial (red) grant receivers. The locations are approximate and the size of the circles represent the number of grants at that institution

APPENDIX 1

109

Raman Raman spectroscopy is a well-established technique for material characterisation, for the purposes of this assessment, projects were analysed which: Developing the technique in unknown configurations Used in conjunction with other techniques to extract new information Develop novel process design, sensor design, enhancing Raman signal with SERS Designing new sources, sensors, analytical methods Projects are NOT included which use the technique as a tool in standard configurations for characterisation.

Key words AHRC

BBSRC

EPSRC

ESRC

MRC

NERC

TSB

STFC

0

7

17

0

3

4

6

23

Number of funded projects in this area since 2006

60

Number of live projects

28

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TML Analysis 15 Total

TSB

12

STFC 9 NERC 6 MRC

Glycan

biologically

EYE Stem cells lidar microscopy

Lipid PAT proteinpollutants

ESRC

3

EPSRC 0

TML 1

TML 2

TML 3

TML 4

TML 5

measurements

dissolution SERS Live Anti Exomars tool

Mars

Procurement

Evaluation

Simple gas-phase

non-invalve

species

REALISTIC Urban

disease RLS Nanosensing monitoring boundary

Scattering

TML 7 BBSRC

Strokes

nanoparticle

TML 6

AHRC

Key InsighTS • Space and EO applications • TSB funded only a few companies • Medical and biological charactisation • STFC funded projects for niche product development for UK Mars missions

Total RCUK Funding: £13,700,211

APPENDIX 1

111

Map of RCUK academic (yellow) and industrial (red) grant receivers. The locations are approximate and the size of the circles represent the number of grants at that institution

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Appendix 2: Inputs into the February Workshop

NAME Moses Ajayi Gordon Attenborough Nicholas Bantin Simon Baty

AFFILIATION University of Lincoln The IET IS – Instruments Bioscience KTN

Devaki Bhatta

Labxero

Matt Butchers

ESP KTN

Andrew Condie Marianne Defernez Roger Dewell

Photonics Analytics Institute of Food Research Interasight

Geoff Diamond

Inspection Technologies

Rachel Hackett

Greencore Group

Gabriel Hamid Victoria Hammond Theresa Huxley Ken Johnston

Bühler Group Smith and Nephew Sainsburys UKTI

Henry Langston

Ocean Optics

Mark Littlewood

ESP KTN

Neil Loxley

Ibex Innovation

Ellen Ni Cleirigh

Nestle

Malcolm Povey

University of Leeds

John Roberts Richard Seager Adrian Stevenson Nigel Stewart Shobitha Sundararajar Richard Turner Jill Webb

Sharp Electronics Marel Labxero AC Goatham Photek University of Lincoln Leatherhead Food Research

APPENDIX 2

113

Trevor Whittley Martin Whitworth

Fibre Photonics Campden BRI

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Appendix 3: Acronyms

2D

Two-dimensional

3D

Three-dimensional

AHRC BBSRC

Arts and Humanities Research Council Biotechnology and Biological Sciences Research Council

ATP

Adenosine triphosphate

CCD

Charge Coupled Device

CT

Computed Tomography

DNA EA

Deoxyribonucleic acid Environment Agency

EDAX

Energy Dispersive X-ray Analysis

ELISA

Enzyme-linked immunosorbent assay

EM

Electromagnetic

EO

Earth Observation

EPSRC ESRC

Engineering and Physical Sciences Research Council Economic and Social Research Council

EVM

Extraneous vegetable matter

FSA

Food Standards Agency

FT-IR H&S HACCP HSI IR

Fourier transform infra-red Health & Safety Hazard Analysis & Critical Control Points Hyperspectral Imaging Infra-red

KTN

Knowledge Transfer Network

MIR

Mid Infra-red

MOD

Ministry of Defence

MRC

Medical Research Council

MRI

Magnetic Resonance Imaging

APPENDIX 3

115

MRSA NDE NERC NIR

Methicillin-resistant Staphylococcus aureus Non-destructive evaluation Natural Environment Research Council Near infra-red

NMR

Nuclear magnetic resonance

PCR

Polymerase chain reaction

PoC

Point of Care

R&D

Research and Development

RADAR

Radio detection ad ranging

RCUK RF

UK Research Councils Radio frequency

RGB

Red Green Blue

RLU

Relative Light Unit

RNA

Ribonucleic acid

SERS SONAR STFC

Surface Enhanced Raman Spectroscopy Sound navigation and ranging Science and Technology Facilities Council

TML

Technology Maturity Level

TSB

Technology Strategy Board

UAV

Unmanned Aerial Vehicle

UK

United Kingdom

UKTI

UK Trade & Investment

VOC

Volatile Organic Compounds

WHO

World Health Organisation

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About The Knowledge Transfer Network

The Knowledge Transfer Network spans the technologies underpinning devices, tools and technologies that are taken for granted today—and that will be taken for granted tomorrow. We are committed to connecting people who don’t usually meet because that’s where the magic happens. Whether this means farmers talking to sensors specialists about sustainable agriculture; or materials scientists talking to laser scientists about 3D printing—we exist to put innovation into practical use

APPENDIX 3

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Knowledge Transfer Network

Knowledge Transfer Network

MATT BUTCHERS

[email protected]

MARK LITTLEWOOD

[email protected]

SIMON BATY

[email protected]