ASSESSMENT OF NUTRITIVE VALUE OF PLANT OILS WITH HIGH CONTENT OF LINOLENIC ACIDS BASED ON THE COMPOSITION OF FATTY ACIDS, TOCOPHEROLS, AND STEROLS

The objective of this study was to assess the nutritive value of plant oils with high content of linolenic acids based on the composition of fatty acids, tocopherols, and sterols. The following cold pressed plant oils were analyzed: flax oil, camelina oil, borage oil, and echium oil, and a refined oil of blackcurrant seeds. The content and composition of fatty acids, tocopherols, and sterols were determined. The oils examined were characterized by a considerable nutritional value owing to the high content of unsaturated fatty acids, especially polyenic acids (50 - 80 %), mainly belonging to an n-3 family. The oils of flax, echium, and camelina A are a good source of acids from the n-3 family. The optimal ratio (4:1) between the acids from the n-6 and n-3 families occurs in the blackcurrant seed oil. The oils of borage, echium, and blackcurrant seeds contain gamma-linolenic and stearidonic fatty acids, which occur rarely and are highly valuable as regards their nutritive value. The blackcurrant seed oil is a significant source of vitamin E. A low Harris coefficient of flax oil, and, also, of camelina, borage, and echium oils prove that those oils should be enriched with vitamin E. The oils analyzed show a relatively low content of phytosterols, and, among them, beta-sitosterol prevails.