Sterol composition of thirty vegetable oils determined by GLC using two phases of different polarity

Abstract

The sterol fraction of 30 fruit and vegetable oils was analysed by GLC using 2 stationary phases of different polarity: JRX (non-polar) and OV 17, and trimethyl silyl (TMS) derivatives and the free-OH form of sterols. Results, presented in tables, showed that no significant quantitative or qualitative differences were found between results for the 2 forms of sterols. The accuracy of the method was confirmed by 15 consecutive analyses of 1 sample of tomato oil. Some interesting relations were found between sterol composition and botanical families, e.g. characteristic Delta 7 sterols were in oils of the Compositae, brassicasterol in the Cruciferae (especially rapeseed oil, (9-12%) and small amounts in the Solanaceae. A similarity in the composition of walnut (Juglandaceae) and avocado (Lauraceae) oil was noted. A difference was observed between the composition of peanut and soybean (Leguminosae) and of coconut, Brazil nut and palm oils (Palmaceae).