The Higher Saturated Fatty Acids of Butter Fat*

Butter fat has been found to be a very complex fat, containing in its glyceride linkages a large number of fatty acids. Since some of these acids are present in very small amounts, they have in the past been frequently overlooked. This is especially true of the fatty acids of higher molecular weight than stearic acid. Hilditch and Jones (l), Hilditch and Sleightholme (2), and others have reported the presence in butter fat of small amounts (0.5 to 1.0 per cent) of saturated fatty acids of higher molecular weight than stearic acid. Since these amounts have been calculated from the mean molecular weights, it has been assumed that this material consisted largely of the next higher acid than stearic acid; i.e., arachidic acid. Bosworth and Brown (3), after a somewhat extended study of the acids derived from their highest boiling methyl ester fraction (230-285’ at 15 mm.) concluded that lignoceric acid and possibly behenic and cerotic acids were present in butter fat. Bosworth and Sisson (4) confirmed the presence of behenic acid.