Acidulant

Acidulants are chemical compounds that give a tart, sour, or acidic flavor to foods or enhance the perceived sweetness of foods.

Acidulants can also function as leavening agents and emulsifiers in some kinds of processed foods.

[1] Though acidulants can lower pH they differ from acidity regulators, which are food additives specifically intended to modify the stability of food or enzymes within it.

Many beverages, such as colas, contain phosphoric acid.

Sour candies often are formulated with malic acid.

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