Glycerol Monostearate

About This Product

Glycerol monostearate is the partial ester of glycerol with stearic acid, produced by esterifying the two principal outputs of fat splitting back together. It is a milky white to pale yellow waxy or powdery solid, odourless and tasteless, freezing point 60-70C, in 25 kg bags. Vegetable-based, from palm-derived fatty acids, in 40% and 90% total monoglyceride grades.

Splitting a triglyceride yields fatty acids and glycerol; re-esterifying those two products gives a partial glyceride with a hydrophilic head and a lipophilic tail, a non-ionic emulsifier made entirely from the same feedstock. It works by sitting at the interface between the phases, the free hydroxyls of the glycerol backbone oriented into the water and the C18 chain into the fat, lowering interfacial tension so droplets resist coalescing. Because only one of the three hydroxyls is esterified the hydrophilic contribution is modest and the HLB is low, in the region of 3.8, which makes it a water-in-oil emulsifier rather than an oil-in-water one and is why it is commonly used as a co-emulsifier alongside a higher-HLB surfactant rather than on its own. The distilled 90% grade carries far less free glycerol and diglyceride than the 40% grade, free glycerin 1.5% maximum against 7.0%, which matters where the emulsifier is a defined component of a formulation rather than a bulk additive.

It is used as a non-ionic emulsifier, in co-emulsifier systems, in personal care formulation and as a surfactant intermediate.

Bio Green Oleo supplies glycerol monostearate to specification on total monoglyceride content, acid value, iodine value, free glycerin and freezing point.