General Description
Synonyms: Acidum malicum; apple acid; E296; 2-hydroxy-1,4-butanedioic acid; hydroxybutanedioic acid; 1-hydroxy-1,2-ethanedicarboxylic acid; hydroxysuccinic acid; 2-hydroxysuccinic acid; DL-malic acid.
Description: White or nearly white, crystalline powder or granules having a slight odor and a strongly acidic taste. It is hygroscopic. The synthetic material produced commercially in Europe and the USA is a racemic mixture, whereas the naturally occurring material found in apples and many other fruits and plants is levorotatory.
Chemical Name: Hydroxybutanedioic acid
Functions
Acidulant; antioxidant; buffering agent; chelating agent; flavoring
agent; therapeutic agent.
Uses
Malic acid is used in pharmaceutical formulations as a generalpurpose acidulant.
It possesses a slight apple flavor and is used as a flavoring agent to mask bitter tastes and provide tartness.
Malic acid is also used as an alternative to citric acid in effervescent powders, mouthwashes, and tooth-cleaning tablets.
In addition, malic acid has chelating and antioxidant properties.
It may be used with butylated hydroxytoluene as a synergist in order to retard oxidation in vegetable oils.
In food products it may be used in concentrations up to 420 ppm.
Therapeutically, malic acid has been used topically in combination with benzoic acid and salicylic acid to treat burns, ulcers, and wounds.
It has also been used orally and parenterally, either intravenously or intramuscularly, in the treatment of liver disorders, and as a sialagogue
Incompatibilities
Malic acid can react with oxidizing materials. Aqueous solutions are mildly corrosive to carbon steels.
Safety
Malic acid is used in oral, topical, and parenteral pharmaceutical formulations in addition to food products, and is generally regarded as a relatively nontoxic and nonirritant material. However, concentrated solutions may be irritant.
Handling Precautions
Observe normal precautions appropriate to the circumstances and quantity of material handled. Malic acid, and concentrated malic acid solutions may be irritant to the skin, eyes, and mucous membranes. Gloves and eye protection are recommended.
Related Substances
Citric acid; fumaric acid; D-malic acid; L-malic acid; tartaric acid.