Products
Pure malic acid is available in specialized stores. The name of the acid is derived from Latin (apple), because it was first isolated from apple juice in 1785.
Structure and properties
Malic acid (C4H6O5, Mr = 134.1 g/mol) is an organic dicarboxylic acid which belongs to the hydroxycarboxylic acids. It exists as a white powder with an acidic and refreshing taste and is readily soluble in water. Malic acid, which is monographed in the pharmacopoeia, is a racemate consisting of the D- and L-enantiomer (D- and L-malic acid). The melting point is about 130 °C. The salts and esters of malic acid are called malates, for example potassium malate, sodium malate and calcium malate. Malic acid is found in numerous fruits, for example apples, quinces, gooseberries and grapes, and gives them their sour taste. It also plays an important role in metabolism, more specifically in the citric acid cycle.
Effects
Malic acid has acidic, preservative, acidity regulating and antimicrobial properties.
Fields of application
- As a pharmaceutical excipient.
- For the production of active ingredient salts.
- As a food additive, for example.
Malic acid is generally used less frequently than other organic acids such as citric acid.
Adverse effects
Pure malic acid can cause severe eye irritation if handled improperly. The appropriate precautions in the safety data sheet must be observed.
