Chemistry of sorbates—a basic perspective∗

Journal Paper No. 13,751 of Purdue Agricultural Experiment Station.

Abstract

Sorbic acid and its potassium and calcium salts are used as preservatives in a large number of foods, feeds, Pharmaceuticals, and cosmetics. In the dry and crystalline state, sorbic acid is stable and no degradation occurs even if stored at room temperature for a long time. However, in solutions and in foods, it undergoes autoxidation during storage, forming carbonyls and other compounds. Many factors (e.g., pH, temperature, packaging, water activity, and composition of food) influence its stability. Degradation of sorbic acid is associated with development of browning in foods. Acetaldehyde and /3‐carboxylacrolein have been reported to be the major degradation products of sorbic acid in aqueous solutions. β‐Carboxylacrolein is found to be responsible for sorbate‐induced browning in foods as it reacts with amino acids and proteins to form brown pigments. Since sorbic acid mainly degrades by autoxidation, deoxygenation and vacuum packaging in oxygen impermeable films or laminates have been suggested to reduce its degradation and ensure adequate shelf‐life of sorbate‐preserved foods.

Notes

Journal Paper No. 13,751 of Purdue Agricultural Experiment Station.