Fatty acid composition of commercial vegetable oils from the French market analysed using a long highly polar column

Abstract

The increasing concern for consumed fat by western populations has raised the question of the level and the quality of fat intake, especially the composition of fatty acids (FA) and their impact on human health. As a consequence, consumers and nutritionists have requested updated publications on FA composition of food containing fat. In the present study, fourteen different kinds of edible oils (rapeseed, olive, hazelnut, argan, groundnut, grape seed, sesame, sunflower, walnut and organic walnut, avocado, wheat germ, and two combined oils) were analysed for FA determination using a BPX-70 60 m highly polar GC column. Oils were classified according to the classification of Dubois et al. (2007, 2008). Monounsaturated FA (MUFA) group oils, including rapeseed, olive, hazelnut, and avocado oils, contained mainly oleic acid (OA). Groundnut and argan oils, also rich in MUFA, showed in addition high linoleic acid (LA) contents. In the polyunsaturated (PUFA) group, grape seed oil presented the highest LA content while sunflower, sesame, and wheat germ oils showed noticeable MUFA amounts in addition to high PUFA contents. Walnut oils, also rich in LA, showed the highest linolenic acid (ALA) content. The n-6/n-3 ratio of each oil was calculated. Trans-FA (TFA) was also detected and quantified. Results were compared with the data published during the past decade, and the slight discrepancies were attributed to differences in origin and variety of seed-cultivars, and in seed and oil processes.

Keywords

• fatty acids
• vegetable oils
• composition
• polar column