Leavening Acid

Leavening Acid. Any of a group of acid-reacting substances used to liberate carbon dioxide gas (q.v.) from the baking soda (q.v.) which has been added to dough (q.v.) or batter (q.v.) to bring about the latter's aeration and expansion. Compounds used for this purpose include monocalcium phosphate (q.v.), sodium acid pyrophosphate (q.v.), sodium aluminum sulfate (q.v.), sodium aluminum phosphate (q.v.), cream of tartar (q.v.), and glucono-delta-lactone (q.v.), among others. The different reaction rates of each of these materials determine their suitability for specific applications.