Calcium Sorbate

Brief Overview 

Calcium sorbate is a calcium salt of sorbic acid. It is a polyunsaturated fatty acid salt and appears as a white crystalline powder. Due to its antimicrobial properties, calcium sorbate is commonly used as a preservative in food and cosmetic products. It is generally non-toxic and safe for exposure. Like other sorbate salts, the primary component of calcium sorbate, sorbic acid, is naturally occurring and can be isolated from Rowan berries.

Manufacturing Process

Calcium hydroxide is added to sorbic acid in a reaction of neutralization. Stoichiometric amounts of calcium hydroxide and sorbic acid are measured and added with precision. To increase the yield of calcium sorbate, sorbic acid is normally added over about 1.05 to 2 times the stoichiometric amount. Other acids like malic acid and lactic acid may be added to lower the pH of the mixture such that an optimal pH is achieved. The reaction mixture is heated to about 80°C and carried out under pressurized conditions. The resulting mixture is then crystallized to obtain solid calcium sorbate. Since solid calcium sorbate is sparingly soluble in water, it is usually coated with a wetting agent before being packaged for commercial purposes.

Food Industry

Calcium sorbate is used in the food industry as an antioxidant and preservative in food products as it can retard microbial growth and mold growth.

Pharmaceutical Industry

Due to its antimicrobial properties, calcium sorbate is used in pharmaceutical packaging products like drugs.