malic acid

chemical compound

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June 30, 2026

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Malic acid is a crystalline dicarboxylic acid with the chemical formula C₄H₆O₅. It is particularly known as the levorotatory isomer found in fruits like apples. Malic acid also plays a role as an intermediate in the Krebs cycle, a key metabolic pathway. The name "malic" originates from the Latin word for apple, malum. It is distinct from malonic acid, which is used in synthesizing vitamins and barbiturates, and maleic acid, which is isomeric with fumaric acid and used in organic synthesis.123

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carboxylic acid
Polycarboxylic acids
Malic acid is found in many fruits, including apples; tartaric acid occurs in grapes; and citric acid is present in lemons, oranges, and other citrus fruits. The monopotassium salt of tartaric acid, commonly called cream of tartar, is obtained from wine casks, where it crystallizes…
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Malic acid is found in many fruits, including apples; tartaric acid occurs in grapes; and citric acid is present in lemons, oranges, and other citrus fruits. The monopotassium salt of tartaric acid, commonly called cream of tartar, is obtained from wine casks, where it crystallizes…
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wine
Malolactic fermentation
…from malolactic fermentation, in which malic acid is broken down into lactic acid and carbon dioxide. The fermentation is caused by enzymes produced by certain lactic-acid bacteria.
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…from malolactic fermentation, in which malic acid is broken down into lactic acid and carbon dioxide. The fermentation is caused by enzymes produced by certain lactic-acid bacteria.
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