Recent research on the origin of milk fat

Abstract

The two main problems of milk-fat secretion are its origin and its difference in composition from body fats. Whereas ox depot fatty acids consist chiefly of stearic, palmitic and oleic acids, cow’s milk fat contains about 10% of the C 4 to C 12 acids (see Hilditch 1956). The problems of origin and composition are, of course, related, and an answer to one is likely to go far in providing an answer to the other. The subject has been extensively reviewed (Folley 1949, 1956; Popják 1951-52, 1952; Shaw & Lakshmanan 1957) and it is intended here to deal only briefly with material that has been discussed in greater detail by others. Further, this review is confined almost entirely to research on the glyceride fat of ruminant milk. Other lipids are present in negligible proportions (Jack & Smith 1956) and space permits reference to other species only for purposes of comparison.