Propylene glycol monostearate

Propylene glycol monostearate (CAS 1323-39-3), commonly abbreviated as PGMS and approved as E477, is a propylene glycol ester of stearic acid used as an emulsifier and plasticizer. It is produced from the esterification of propylene glycol with stearic acid, yielding a mono-ester with moderate hydrophilic-lipophilic balance suited to oil-in-water and water-in-oil systems.

In food manufacturing, PGMS functions as an aerating emulsifier in cake mixes, whipped toppings, and bakery shortenings, improving volume and crumb structure for better consumer appeal. Personal care formulators incorporate it into creams and lotions to stabilize emulsions and modify texture, contributing to a smooth, non-greasy skin feel in various cosmetic products.

Pharmaceutical manufacturers use it as a plasticizer and emulsifying agent in topical formulations and tablet coatings where controlled release and consistency are required for safety. In plastics processing, PGMS acts as an internal lubricant and softener, reducing melt viscosity and improving surface finish in polymer extrusion and other industrial manufacturing processes.

PGMS is supplied as white to off-white flakes or a waxy solid. Food-grade material conforming to FCC and E477 specifications is the most commonly traded form for global distribution. Typical commercial grades are characterized by their mono-ester content, acid value, and iodine value to confirm purity and performance consistency across different industrial applications.