Feeding lactating Holstein cows a lipid source high in palmitic acid changes the fatty acid composition and thermal properties of lipids in milk and butter

The aim was to determine the effect of feeding either a low (121.2 g/kg of DM) or a high (793.1 g/kg of DM) palmitic acid supplemental fat to lactating Holstein cows on milk yield and composition and changes in thermal properties of the milk fat. There are numerous studies reporting the effect of dietary lipids high in palmitic acid on animal performance, but few reports determined the effect on the thermal properties of the milk fat produced. Cows fed the high palmitic diet showed increased (P < 0.001) fat content and produced more 4% FCM. Concentration of palmitic acid in milk was greater (P < 0.001) for the high palmitic than low palmitic diet. Textural analysis of butter showed that anhydrous milk fat from high palmitic cows was harder (P < 0.001) at both ambient and 10°C temperatures compared with that from low palmitic cows. Temperatures at onset of melting and peak of melting of butter from high palmitic cows were greater than low palmitic cows. Feeding a high palmitic acid supplement to lactating cows changed the fatty acid composition of milk lipids and modified their functional property, which was illustrated by a harder butter. The implications are that feeding lipid supplements high in palmitic acid could affect the physicochemical properties of dairy products, butter in particular, but also potentially other dairy products that contain milk fat.