Abstract

Glycerol, a trihydric alcohol, is a clear, water-white, viscous, sweet-tasting hygroscopic liquid at ordinary room temperatures above its melting point. Glycerol occurs naturally in combined form as glycerides in all animal and vegetable fats and oils, and is recovered as a by-product when these oils are saponified in the process of manufacturing soap, when the fats are split in the production of fatty acids, or when fats are esterified with methanol in the production of methyl esters. Since 1949 it has also been produced commercially by synthesis from propylene.

The uses of glycerol number in the thousands, with large amounts going into the manufacture of drugs, cosmetics, toothpastes, urethane foam, synthetic resins, and ester gums. Tobacco processing and foods also consume large amounts either as glycerol or glycerides.

Glycerol, is generally recognized as safe (GRAS) as a miscellaneous or general-purpose food additive and it is permitted in certain food packaging materials. Glycerol derivatives include acetals, amines, esters, and ethers. Glyceryl trinitrate (nitroglycerin) is used in explosives and as a heart stimulant. Included among the esters also are the ester gums and, mono- and diglycerides used as emulsifiers and in shortenings. The salts of glycerophosphoric acid are used medicinally.