Calcium formate

Calcium formate, - calcium salt of formic acid, HCOOH. Also known as food additive E238 in the food industry. Under this E number it is used as an animal feed preservative within EU, but not in foods intended for people. In nature, it is extremely rare in some minerals.


Calcium formate is stable at room temperature, is inflammable and forms orthorhombic crystals. The mineral form is very rare and called formicaite, and is known from a few boron deposits.

Uses of Calcium Formate

Calcium formate is used within EU as an animal feed preservative. It acidifies the feed thus preventing microbe growth and increasing shelf life. About 15 g of csalcium formate addition per kg of feed lowers its pH by one. 15 g/kg is the maximum recommended feed concentration within EU – this level is thought to be safe for pigs, chickens, fish and ruminants. The compound is not environmentally harmful in feed use at these levels. Calcium formate prevents the growth bacteria such as E. coli, Pseudomonas aeruginosa, Staphylococcus aureus and Enterococcus hirae in growth mediums. It also prevents the growth of fungi like Aspergillus niger and Candida albicans. However, the relevance of these experimental observations to feed preservation is not known.

Calcium formate is used as a masking agent in the chrome tanning of leather. Calcium formate in tannage formulation promotes faster, more efficient leather penetration of the chrome. Calcium formate can also be used as a replacement for formic acid in the pickling operation.

As a grout and cement additive, calcium formate imparts a number of desirable properties in the final product, e.g. increased hardness and decreased setting time. Its addition is desirable for work at low temperature and for inhibition of corrosion of metal substrates within cement/grout. It is also effective in the prevention of efflorescence. In drywall (gypsum board), calcium formate can functions as a fire retardant.

Calcium formate and urea mixtures are effective deicers, and tend to cause less corrosion of steel and cement surfaces relative to some other deicers.