1. Food Acids
Food acids are added in order to make the flavours of the food to be 'sharper' or to have a 'stronger taste'. Food acids also act as preservatives and antioxidants.
Food acids do occur naturally. These acids in natural food products give them a distinct flavour or tinge. Some examples of naturally occurring acids in foods are citric acid, malic acid and tartaric acid.
*Naturally Occurring Food Acids
a. Citric Acid - Citrus Fruits (Lime, Lemon, Orange)
b. Malic Acid - Apple
c. Tartric Acid - Grapes, Pineapples, Potatoes, Carrots
d. Acetic Acid - Vinegar
e. Oxalic Acid - Tea, Cocoa, Pepper
f. Tannic Acid - Tea
g. Caffeotannic Acid - Coffee
h. Benzoic Acid - Cranberries, Prunes, Plums
i. Butyric Acid - Decomposition of Butter
j. Lactic Acid - Milk Digestion
(*taken from HERE)
The Production of Citric Acid as Food Additive
Naturally, citric acid is found in citrus fruits especially lemons, limes and oranges. It is interesting to note that citric acid is produced by going through the citric acid cycle. Mold and bacteria also produce citric acid!
Citric acid is used for its sour flavour, the ability to preserve foods and acts as a pH buffer. Thus, citric acid is added to many manufactured food products.
In 1917, an American food chemist by the name of James Currie, discovered that the mold, Aspergillus niger was able to produce citric acid by metabolizing sucrose or glucose. And this method was efficient and cheap! Thus it became a profitable business.
Citric acid is used as a flavour enhancer in beverages. It is used in soft drinks, teas, and juices to create a slightly tart flavour.
The pH which is acidic also functions as a preservative as many bacteria are unable to thrive in an acidic environment. Thus it is suitable to be used in jams, jellies, candy, canned foods and meat products.
Citric acid can be used in dry foods too as it can be produced in powder form.
The E number of citric acid is E330.
The Production of Malic Acid as Food Additive
Malic acid contributes to the sourness of green apples. It is also present in grapes and in most wines. In rhubarb, the taste of malice acid is very sharp and clear.
It is used as an artificial vinegar flavour in 'Salt & Vinegar' flavoured potato chips.
The E number for malic acid is E296.
To read more about malic acid, click on LINK.
The Production of Tartric Acid as Food Additive
Naturally, tartaric acid occurs in grapes, bananas and tamarinds.
In baking, tartaric acid is combined with baking soda to form baking powder, which is a leavening agent.
Tartaric acid is used as a food additive in sour-tasting sweets.
In the pharmaceutical industry, tartaric acid combined with citric acid is used to improve the taste of oral medication.
*It is very interesting to note that tartaric acid is a muscle toxin which inhibits the production of malic acid and when used in high doses causes paralysis and death! (*taken from HERE)
The E number for tartaric acid is E334.
The Production of Acetic Acid as Food Additive
This acid has a very pungent smell and a distinctive sour taste.
In the food industry, acetic acid is labelled as E260. It is used as an acidity regulator and as a condiment. It is also used in pickled food.
To read more on acetic acid, click on LINK.
The Production of Tannic Acid as Food Additive
*Tannic acid is the commercial form of tannin which is the basic ingredient in the chemical staining of wood. This occurs naturally in oak, walnut and mahogany.
In food, tannic acid is used in processing beer. It is also used as an aroma compound in soft drinks and juices. In the wine industry, it is used as a colour stabiliser and taste enhancer.
Interestingly, it currently does not hold an Enumber as it is not considered as a food additive but as a food ingredient.
In the pharmaceutical industry, tannic acid is used to produce albumin tannate which is used as an anti-diarrhoea agent. It is also used in some anti-histamines to either act as a stabiliser or as a slow-release.
(*take from HERE)
The Production of Benzoic Acid as Food Additive
Benzoic acid is found naturally in berries. It is even produced by certain species of animals!
This acid is used in dried and pickled food products.
*In the pharmaceutical industry, benzoic acid is combined together with salicylic acid to treat skin irritation and inflammation caused by burns, insect bites, fungal infarctions and eczema.
(*taken from HERE)
The E number of benzoic acid is E210.
To read more about citric acids in food production, click on LINK and LINK.