Sorbitan monostearate is a fatty acid ester used as a nonionic surfactant and emulsifier. It stabilises water-in-oil emulsions. It is used in food, cosmetics and pharmaceuticals. It also serves as a thickening agent. Its appearance is cream to tan waxy solid flakes or beads. The catalogue lists food, pharmaceutical and cosmetic grades in 25 kg bags, 25 kg fibreboard drums, 200 kg drums, 500 kg big bags and 1000 kg IBCs. Food use as E 491 is subject to the applicable food-additive specification and permitted-use conditions. Cosmetic use is subject to the applicable cosmetic-ingredient conditions. Pharmaceutical use requires the applicable pharmacopoeia grade.