A comparative study of fatty acid profiles in ruminant and non‐ruminant milk

This is a comprehensive study of fatty acid (FA) profiles in milk from bovine, caprine, ovine, asine, and equine species. Milks from these species are universally common as constituents in a variety of different food and dairy products. We have obtained structural information on FAs, and discussed their correlation to health effects. The extracted fat from all species were derivatized to FA methyl esters for analysis by GC-MS. Large differences in the lipid content and FA composition between ruminants and non-ruminants were observed. Ovine milk showed the highest lipid content of all the animals tested, both ruminants and non-ruminants. Among the ruminants, bovine milk was richer in saturated FAs (69.7%) than ovine- and caprine milk (57.5 and 59.9%, respectively). Ovine milk contained the highest amounts of monounsaturated FAs (39.1%) and also odd- and branched-chain FAs (5.5%). Milk from the monogastric animals, mares and donkeys, were highest in polyunsaturated FAs with a content of 19.3 and 14.2%, respectively. The assumed health negative trans FAs were analyzed to be highest in the ruminant milk (0.7–1.0%). Milk from these species contained also the highest amount of the health beneficial CLA (0.4–0.7%). Practical applications: This is a comprehensive study of milk from five species analyzed under identical conditions. The different fatty acids and their derivatives are increasingly important components because of the contradictory reports on positive and negative effects on human health. New information on the composition of milk from different species is of great importance. The results may give valuable information to producers and nutritional advisors on the consumption of milk and milk products.