lactic acid

Organic acid that occurs as colourless, almost odourless crystals or liquid, produced by certain bacteria during fermentation and by active muscle cells when they are exercised hard and are experiencing oxygen debt. An accumulation of lactic acid in the muscles may cause cramp. It occurs in yogurt, buttermilk, sour cream, poor wine, and certain plant extracts, and is used in food preservation and in the preparation of pharmaceuticals. It may also be referred to as ‘lactate’, which is the name of its anion and of any salts it forms, for example sodium lactate.