Malic acid is an alpha-hydroxy acid of formula HOOC-CH2-CHOH-COOH. It is a dicarboxylic acid very common in the plant kingdom and naturally present in apples, pears and grape juice, which it contributes to the pleasant flavor. It is therefore used as a food additive, under the number E296. There exist in the form of two diastereoisomers, the enantiomers L and D; only L-malic acid is present in the natural environment
Malic acid contributes to the acidity of green apple juice.