Propylene glycol is a colorless, viscous liquid. It has a wide range of applications including industrial solvents, paint and coating solvents, polyester and alkyd resins, antifreeze coolants, heat transfer fluids, deicing fluids, plasticizers, detergents and surfactants, and bactericide. USP grade is used in foods, pharmaceutical, and personal care products. Propylene glycol monostearate is not approved in Germany.
Propylene glycol monostearate (PGMS) is only slightly water dispersible, but completely soluble in fats and oils, therefore it is used only in combination with oils and fats as an emulsifier and emulsion stabilizer. In food it is mainly used in cake batters, cake icings, cake shortening, margarine, oils, oleomargarine, poultry fat, whipped toppings, icecream, and yeast. As a defoamer, it is used in food-contact paper and paperboard. In cosmetic industry it is used as an emulsifier for lotions, soft cream, makeup, humectant in dry skin products.
As most emulsifiers can decrease the amount of fat or oil in the product or add bulkiness or soften texture by increasing the amount of air suspended throughout the product, emulsifiers can serve to some degree as substitutes for fat and can decrease calories. Emulsifiers can be divided in natural and synthetic. Within the natural emulsifiers, the lecithins are by far the main products. Raw lecithin is produced mainly from soybeans. Lecithin is the most widely used chocolate emulsifier. Other important applications include baked goods and dairy products.
Propylene glycol monostearate is used in cake batter and icing
(Adapted from: "Processing fruits: science and technology". Diane M. Barrett, László P. Somogyi, Hosahalli S. Ramaswamy)