Factors Influencing the Concentration of Certain Liposoluble Components in Cow and Goat Milk: A Review

Abstract

Milk fat contains a large number of fatty acids (FA) and other liposoluble components that exhibit various effects on human health. The present article reviews some of the factors affecting FA, vitamin A and cholesterol concentrations in milk from dairy cow and goat. Milk fat composition is linked to many factors, both intrinsic (animal species, breed, lactation stage) and extrinsic (environmental). The effect of animal species on milk fat composition is important, as reflected by higher concentrations of short- and medium-chain FA, vitamin A and cholesterol in goat than in cow milk. In a given ruminant species, the effects linked to breed are significant but limited and they can only be achieved over long periods of time. The lactation stage has an important effect on milk FA composition, mainly linked to body fat mobilisation in early lactation, but it only lasts a few weeks each year. Furthermore, changes in feeding have a marked influence on milk fat composition. Changing the forages in the diet of ruminants, pasture in particular, or supplementing lipids to the diet, represent an efficient mean to modify milk fat composition by decreasing saturated FA and cholesterol, and increasing cis-9,trans-11-CLA and vitamin A. Nutrition therefore constitutes a natural strategy to rapidly modulate milk FA, vitamin A and cholesterol composition, with the overall aim of improving the long-term health of consumers.