This was the first food acidulant to be used in significant quantities although its use has now been mostly replaced by citric acid. The largest single application for tartaric acid is as a raw material for the manufacture of the emulsifiers bread improvers .
Tartaric acid can be manufactured by natural and synthetic routes. The natural route involves the recovery of tartaric acid from wine. The synthetic route involves the chemical reactions of maleic anhydride.
An important salt of tartaric acid, potassium hydrogen tartrate (or cream of tartar), has applications as an acidulant for baking powder and sugar confectionery. Tartaric acid is a white crystalline diprotic acid. This aldaric acid occurs naturally in many plants, particularly grapes, bananas, and tamarinds, is commonly combined with baking soda to function as a leavening agent in recipes, and is one of the main acids found in wine.
It is added to other foods to give a sour taste, and is used as an antioxidant. Salts of tartaric acid are known as tartrates.
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