Products
Adipic acid is used as an excipient in pharmaceuticals and as an additive in foods. It was originally produced from fats (adeps).
Structure and properties
Adipic acid (C6H10O4, Mr = 146.14 g/mol) exists as a white crystalline, odorless and poorly hygroscopic powder and is sparingly soluble in water. In boiling water the solubility is increased. It is an unbranched and saturated dicarboxylic acid that occurs naturally and is produced synthetically. The acid melts from about 151 °C. Structure: HOOC-(CH2)4-COOH Its salts and esters are called adipates. The salts include sodium adipate (E 356) and potassium adipate (E 357).
Effects
Adipic acid has acidic properties and a persistent sour taste. The pKa values are 4.4 and 5.4.
Indications for use
- As a pharmaceutical excipient, for example for tablets.
- As a food additive, for example, as an acidifier and acidity regulator for desserts, for the preparation of baking powder.
Adverse effects
Pure adipic acid is irritant and may cause severe eye irritation in case of accidental contact. The appropriate precautions in the Material Safety Data Sheet must be observed.
