Malic acid is a tart-tasting organic acid that plays a role in many sour or tart foods. The chemical structure of malic acid is HO2C-CH2-CH(OH)-CO2H.
Apples contain malic acid, which contributes to the sourness of a green apple.
Malic acid can make a wine taste tart, although the amount decreases with increasing fruit ripeness. The process of malolactic fermentation converts malic acid to much milder lactic acid.
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