What is it?
The monoester of glycerin and caprylic acid, a medium-chain fatty acid found in coconut oil. In skin care, makeup and deodorants it works as an emollient and emulsifier, and it also has antimicrobial activity, so it helps protect formulas from microbes, including “self-preserving” products made without conventional preservatives.
Key information
- The CIR Expert Panel has concluded that glyceryl caprylate is safe in the present practices of use and concentration.
- In 2015 it was reported in 190 cosmetic products, at up to 1.5 percent.
- At 15 percent it caused no irritation or allergic sensitization in a repeat patch test of 63 volunteers.
- The authors of a 2026 survey of cosmetic preservatives wrote that contact allergy to it appears to be rare.
More information
Monoglycerides such as glyceryl caprylate are made by esterifying glycerin with a fatty acid, which gives a mixture of mono-, di- and triglycerides depending on the proportions used. Because it has antimicrobial activity, glyceryl caprylate is one of the ingredients that let some products do without conventional preservatives. A 2026 study of leave-on cosmetics sold in the Netherlands listed it, with caprylyl glycol and ethylhexylglycerin, among the multifunctional antimicrobial ingredients used in self-preserving formulas.
The Cosmetic Ingredient Review (CIR) Expert Panel concluded in 2004 that glyceryl caprylate is safe as used, and reached the same conclusion in its amended review of the monoglyceryl monoesters, published in 2020. Industry data then listed it in 190 products at 0.001 to 1.5 percent. In a repeat insult patch test, 15 percent glyceryl caprylate caused no irritation or allergic sensitization in the 58 of 63 volunteers who completed the study. The panel noted that monoglycerides can help other ingredients pass into the skin, a point for formulators.
Allergy is possible but uncommon. The CIR review describes a woman with facial eczema that followed use of a skin cream; patch tests showed a strong allergic reaction to glyceryl caprylate at 1 and 5 percent and a weaker one at 0.1 percent, while three control subjects did not react. The authors of the 2026 survey wrote that contact allergy to glyceryl caprylate appears to be rare.
On labels it appears as “glyceryl caprylate.” It is not ethoxylated and is unrelated to the PEG family.
Sources: Cosmetic Ingredient Review: Safety assessment of monoglyceryl monoesters as used in cosmetics (draft final amended report, 2015); Cosmetic Ingredient Review: Quick reference table of safety conclusions (September 2022); Contact Dermatitis (2026): Preservatives in leave-on cosmetics available on the Dutch market
