Food acids are the only edible acids. The sharpness in the taste of any food is due to the presence of these acids. All fruits have these acids in some quantity and the result is that typical taste.

The naturally occurring food acids are citric acid, malic acid and tartaric acid. They are also called wholesome acids. They are found in oranges, grapefruits, pineapples, apples, peaches and other seeded fruits. Tartaric acid is found in grapes, pineapples and potatoes. Without the presence of these acids these fruits may taste bland.

These food acids are available from the natural resources except phosphoric acid. The presence of acid in a fruit determines many things like food preservation and jam and jelly setting etc. These acids have antioxidant and preservation properties as well. The most commonly used food acid is citric acid. Phosphoric acid is used in aerated drinks along with carbon dioxide.

Acid	Source
Citric Acid	Citrus fruits- lemon, orange
Malic Acid	Apple
Tartric Acid	Grapes, pineapples, potatoes, carrots
Acetic Acid	Vinager
Oxalic Acid	Tea, cocoa, pepper
Tannic Acid	Tea
Caffeotannic Avid	Coffee
Benzoic acid	Cranberries, prunes and plums
Butyric acid	decomposition of butter
Lactic acid	Milk Digestion