Calcium benzoate Calcium benzoate Calcium benzoate refers to the calcium salt of benzoic acid. When used in the food industry as a preservative, its E number is E213 (INS number 213); it is approved for use as a food additive in the EU, USA and Australia and New Zealand. The formulas and structures of calcium carboxylate derivatives of calcium and related metals are complex. Generally the coordination number is eight and the carboxylates form Ca-O bonds. Another variable is the degree of hydration. It is preferentially used more than other benzoic acid salts or its esters in foods due to its better
Calcium nitrite by different synthesis processes. One is by reacting hydrated lime with NOX gas, which typically comes from a nitric acid plant. At the acid plant, ammonia is burned to produce the NO gas for acid as well as calcium nitrite. Also, it can be prepared as detailed below, forming a solution of sodium nitrite and calcium nitrate; cooling the solution to precipitate sodium nitrate; forming a double salt of calcium nitrite/calcium hydroxide; and in the presence of water, decomposing double salt to form a solution of calcium nitrite and insolubilize calcium hydroxide. Essentially the function of calcium hydroxide is to