Abstract The compositions of acyl lipids, fatty acids and tocopherols were determined for a series of laboratory‐extracted and commercial wheat germ oils and a comparison made of the total carotenoid contents. High‐performance liquid chromatography (h.p.l.c.) with fluorescence detection was used to determine tocopherols and tocotrienols without the need for pretreatment of the oils. The laboratory‐extracted oils were similar in composition except for the content of free fatty acids and the β‐tocotrienol derived from bran in the unpurified mill germ; carotenoid content was lower in oil from rancid or cooked germ. The commercial oils contained very low concentrations of carotenoids and polar lipids and three samples had unusual tocopherol compositions very different from those of the laboratory‐extracted oils. One of these samples contained no detectable amount of linolenic acid which is usually present in cereal oils. It is concluded that the quality and composition of commercial wheat germ oil is very variable and that methods of assessing quality and detecting adulteration are essential. H.p.l.c. with fluorescence detection is well‐suited to the analysis of tocopherols, tocotrienols and α‐tocopherol acetate in wheat germ oil.
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