ACIDITY

Pamantasan ng Lungsod ng Maynila College of Engineering and Technology ESC313-Engineering Probability and Statistics

“An Analysis on the Acidity of Different Local Brands of Vinegar” A Case Study

Prepared By: Ang, Quennie Ann

Gamet, Arnold

Paras, Jorjan

Besa, Rose Lynn Anne

Haro, April Joy

San Juan, Elline Lizette

De Castro, Raymond

Lim, Gerald

Yanguas, Julius

BSChE-III

Submitted to: Engr. Reynaldo Ted L. Penas Project Study

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Pamantasan ng Lungsod ng Maynila College of Engineering and Technology ESC313-Engineering Probability and Statistics Acknowledgement

The researchers have taken efforts in this project. However, it would not have been possible without the kind support and help of many individuals and organization. At the completion of this Case Study, they would like to extend their sincere thanks to all of them.

The researchers are highly indebted to the College of Science faculty as well as the personnel of the Science Laboratory System for their guidance and constant supervision as well as for providing necessary equipments and apparatus regarding the project & also for their support in completing the project.

They would also like to express their gratitude towards their professor for the course, Engr. Reynaldo Ted L. Penas, for his ingenuity in teaching and for giving them the opportunity to put into practice the applications of Probability and Statistics which served as a tool for the fulfillment of the project. Their thanks and appreciations also go to their classmates who have willingly helped them out with their abilities.

And most of all, to our Heavenly Father in whom they owe everything - for the wisdom, grace, guidance and supplication. All glory and power belongs to Him alone.

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Pamantasan ng Lungsod ng Maynila College of Engineering and Technology ESC313-Engineering Probability and Statistics I.

INTRODUCTION Introduction

Vinegar is a common ingredient in Filipino cuisine being a fundamental ingredient in many basic Philippine preparations usually derived from sugar cane, coconut, or nipa. It is formed by aerobic bacteria oxidizing grain alcohol to acetic acid and water. More generally, vinegar can be defined as a solution composed of acetic acid (HC2H3O2), water, and, perhaps, other substances. To be sold in stores as vinegar, this solution must contain at least four grams of acetic acid per 100 ml of solution.

The defining characteristic of paksiw dishes is their use of vinegar. Adobo and kinilaw use vinegar as well. Vinegar is also a common condiment at the Filipino dining table where it is commonly mixed with crushed garlic, soy sauce, siling labuyo, or some combination thereof as a dipping sauce to accompany a meal of fried fish, steamed shrimps or crabs, grilled liempo or crispy pata. Such flavored or spiced vinegar(sinamak) is also sold pre-prepared in supermarkets. Local brands include Datu Puti, Amihan, Silver Swan, Marca Piña, Lorins, Supremo, Tentay, Mother's Best, and Del Monte.

There are many different types of vinegar that you can buy to use around the kitchen for cooking and pickling. The chemical compound that gives vinegar its tart taste and pungent smell is acetic acid. Do different vinegars have different amounts of acetic acid? How much variation is there between the different types? This study aims to find out the answer to these questions. In determining the acid concentration of a sample, the researchers has used acid-base titration through the use of the probe and meter which is the most accurate and reliable method of pH determination. This study, entitled “An Analysis of the Acidity of Different Local Brands of Vinegar”, therefore, aims to determine and compare the acidity of six(6) locally-manufactured brands of vinegar.

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Pamantasan ng Lungsod ng Maynila College of Engineering and Technology ESC313-Engineering Probability and Statistics Background of the Study

Vinegar is one of nature's great gifts to mankind, and vinegar history shows us why. Any alcoholic beverage, whether it is made from apples, grapes, dates, rice or plain white sugar, once exposed to air, will turn naturally to vinegar. It is the ever-present bacteria in the air that converts the alcohol in cider, wine, and beer, into acetic acid, which gives vinegar its characteristic sharp sour taste. So it is safe to say that man has been exposed to vinegar since before recorded vinegar history.

Recorded vinegar history starts around 5000 BC, when the Babylonians were using the fruit of the date palm to make wine and vinegar. They used it as a food and as a preserving or pickling agent. Vinegar residues have been found in ancient Egyptian urns traced to 3000 BC. As well, recorded vinegar history in China starts from texts that date back to 1200 BC.

The physical and chemical properties of vinegar reflect the fact that vinegar is mainly a dilute aqueous solution of acetic acid.

This acid liquid which we call vinegar, is the product of two biochemical processes:

Alcoholic fermentation, which converts natural sugars into alcohol.

Acid fermentation in which acetobacter, microorganisms present in the air we breathe, converts the alcohol into acid.

And it is this acid, which imparts the sour taste to vinegar along with its cleaning and antiseptic or germ killing properties.

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Pamantasan ng Lungsod ng Maynila College of Engineering and Technology ESC313-Engineering Probability and Statistics

As far as chemical reactions are concerned, vinegar is a dilute solution of acetic acid, so it has the same

chemical

formula

as

acetic

acid.

A molecule of acetic acid contains two carbon, four hydrogen and two oxygen atoms which is often written as CH3COOH to reflect its actual molecular structure:

Molecular Structure of Vinegar

The pH value or potentiometric hydrogen ion concentration of a solution basically determines how acidic or basic the solution is. The pH value of any solution is evaluated in a logarithmic scale, rating 0.0 to be most acidic, 14.0 most basic or alkaline and 7.0 to be the neutral point. Hence, in order to decide whether a solution is acidic, basic or neutral in nature, one has to know its pH value. The pH value of any solution is measured by calculating the concentration of hydrogen ions (H+) and hydroxyl ions (OH-) present in it. Mathematically, the pH equates to the negative logarithm (base 10) of the hydrogen ion concentration in moles per liter. Hence, if the pH of a solution falls by 1 pH unit, its hydrogen ion concentration

increases

by

ten

times.

A solution having increased level of hydrogen ions implies that it is acidic in nature whereas less hydrogen ions (H+) and more hydroxyl ions (OH-) show that the solution is more basic or alkaline in nature. However, if both the hydrogen (H+) and hydroxyl ion (OH-) levels are approximately equal, it implies that the solution is neutral. The pH of vinegar depends upon how much acid is present in it. The most commercial distilled white vinegars contain 5% acetic acid and so have a pH value that is somewhere between 2.40 - 3.40.

A pH meter is an electronic device used for measuring the pH (acidity or alkalinity) of a liquid (though special probes are sometimes used to measure the pH of semi-solid substances). A typical pH Project Study

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Pamantasan ng Lungsod ng Maynila College of Engineering and Technology ESC313-Engineering Probability and Statistics meter consists of a special measuring probe (a glass electrode) connected to an electronic meter that measures and displays the pH reading.

A pH Meter

The basic principle of the pH meter is to measure the concentration of hydrogen ions. Acids dissolve in water forming positively charged hydrogen ions (H+). The greater this concentration of hydrogen ions, the stronger the acid is. Similarly alkalis or bases dissolve in water forming negatively charged hydrogen ions (OH-). The stronger a base is the higher the concentration of negatively charged hydrogen ions there are. The amount of these hydrogen ions present solution is dissolved in some amount of water determines the pH.

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Pamantasan ng Lungsod ng Maynila College of Engineering and Technology ESC313-Engineering Probability and Statistics OBJECTIVES OF THE STUDY The study entitled “An Analysis of the Acidity of Different Brands of Locally-Manufactured Vinegar” has the general and specific objectives of coming up with an alternative source of paper that is cheaper and strong paper. As far as chemical reactions are concerned, vinegar is a dilute solution of acetic acid, so it has the same chemical formula as acetic acid. The pH value or potentiometric hydrogen ion concentration of a solution basically determines how acidic or basic the solution is. This idea was the basis of this study and experimentation.

The researchers had the following objectives: General: The study aims to evaluate the pH levels of different brands of commercial vinegars produced locally in the Philippines. Specific: 1. To measure the total acid concentration in specific brands of vinegar using acid-base titration 2. To compare the pH of each brand through the use of probability and statistics 3. To determine if the vinegar meets the minimum acetic acid content specified by commercial law 4. To calculate the percent acetic acid to test the authenticity of the total acidity declared on the vinegar's label

(pra sa RRL) This is the standard specifications for vinegar. The regulation was published by Department of Health under ADMINISTRATIVE ORDER NO. 134 s. 1970 with the subject “Regulation Prescribing the Standard of Identity and Quality of Vinegar”

1. Identity

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Pamantasan ng Lungsod ng Maynila College of Engineering and Technology ESC313-Engineering Probability and Statistics a) Vinegar is the liquid produced by alcoholic and/or acetous fermentations of one or more of the following: malt, spirit, wine, cider, alcoholic liquors, fruits, grain, vegetables, honey, glucose, sugar (including unrefined crystal sugar and refinery syrups) or molasses. cane juice, sucrose, molasses or refiner’s sugar. 2. Malt vinegar is the product made by the alcoholic and subsequent acetous fermentation of barley malt, or cereals whose starch has been converted to malt. 3. Coco vinegar is the product made by the alcoholic and subsequent acetous fermentations of the sap of coconut palm. 4. Pineapple vinegar is the product made by the alcoholic and subsequent acetous fermentations of pineapple juice. 5. Nipa-sap vinegar (sucang puti, native vinegar) is the product made by the alcoholic and subsequent acetous fermentations of the sap of nipa palm (Nipa fruticans Worm)

5. b) Distilled vinegar is the liquid produced by acetous fermentation of dilute distilled alcohol or by the distillation of vinegar. 6. 2. Optional ingredients 7. a) Caramel may be used as a coloring in any variety of vinegar without declaration on the label. b) Flavoring may be used in any variety of vinegar, provided its nature is declared on the label.

8. 3. Standard of Quality 9. a) All vinegar shall have an acidity of not less than 4% by weight of absolute acetic acid except nipa sap vinegar which shall have an acidity of not less than 3%. b) All vinegar shall contain not less than 1.5% w/v of total solids and 0.18% of ash, except nipasap vinegar which shall contain not less than 2.2% of solids and not less than 0.4% of ash. c) All vinegar shall contain foreign substances, drugs, sulfuric acid or other mineral acids. d) All vinegar shall contain not more than 18 parts per million of lead, 66 parts per million of copper and 1.5 parts per million of arsenic. e) Malt vinegar shall have at least 0.05% of phosphorous pentoxide (P2O5) and 0.4% of nitrogen. f) Vinegar containing any artificial matter such as synthetic acetic acid, or cloudifying agent shall

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Pamantasan ng Lungsod ng Maynila College of Engineering and Technology ESC313-Engineering Probability and Statistics be deemed to be adulterated and its sale is thereby prohibited.

References: http://www.apple-cider-vinegar-benefits.com/properties-of-vinegar.html http://www.buzzle.com/articles/vinegar-ph-of-vinegar.html http://discoverhydroponics.com/how-do-ph-meters-work/ http://en.wikipedia.org/wiki/PH_meter http://www.titrations.info/acid-base-titration-acetic-acid-in-vinegar Allgeier RJ et al., Newer Developments in Vinegar Manufacture, 1960 ("manufacture of white or spirit vinegar"), in Umbreit WW, Advances in Microbiology: Volume 2, Elsevier/Academic Press Inc.,

http://philfoodie.blogspot.com/2011/08/philippine-vinegar.html

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