Acidulant

Acidulants are chemical compounds that confer a tart, sour, or acidic flavor to foods. They differ from acidity regulators, which are food additives intended to modify the stability of food or enzymes within it. Typical acidulants are acetic acid (e.g. in pickles) and citric acid. Many beverages, such as colas, contain phosphoric acid. Sour candies often are formulated with malic acid.[1]

Malic acid is added to some confectionaries to confer sour flavor.