Glycerol monostearate exists as three stereoisomers, the enantiomeric pair of 1-glycerol monostearate and 2-glycerol monostearate. Typically these are encountered as a mixture as many of their properties are similar.
Commercial material used in foods is produced industrially by a glycerolysis reaction between triglycerides (from either vegetable or animal fats) and glycerol.
Glycerol monostearate occurs naturally in the body as a product of the breakdown of fats by pancreatic lipase. It is present at very low levels in certain seed oils.
GMS is a food additive used as a thickening, emulsifying, anticaking, and preservative agent; an emulsifying agent for oils, waxes, and solvents; a protective coating for hygroscopic powders; a solidifier and control release agent in pharmaceuticals; and a resin lubricant. It is also used in cosmetics and hair-care products.
GMS is largely used in baking preparations to add "body" to the food. It is somewhat responsible for giving ice cream and whipped cream their smooth texture. It is sometimes used as an antistaling agent in bread.