Determination of Fatty Acids and Sterols in Some Vegetable Oils by Capillary Gas Chromatography

Abstract

Capillary gas liquid chromatography (GLC) was conducted to determine fatty acid methyl ester and TMS sterol content in four different vegetable oils : soybean, cottonseed, sunflower, and grapeseed oils. GLC was efficient not only for attaining high resolution but also in detecting minor constituents of the oils. Each oil could be distinguished from the others by comparing fatty acid and sterol patterns. When there was case of similarity, the relative ratio of as the ratio of polyunsaturates % to total saturates % as well as the ratio of β-sitosterol to the sum of campesterol and stigmasterol could be used to accurately evaluate the authenticity of each oil.