Modern Views on the Physical Structure of the Membrane of the Fat Globules in Milk and Cream and a Possible Relation with the Migration of Copper During Butter Manufacture

The different models proposed in the literature for the membrane of the milk fat globules are reviewed. On the basis of recent investigations, in particular of those of S. Hayashi, a new model is proposed, according to which the membrane is constituted by two layers which can easily be fractionated. The inner layer of cytoplasmic origin has a matrix structure, constituted by a complex lipid‐protein aggregate. On this inner membrane an outer layer composed of numerous lipoprotein particles is associated. This new model will enable a better understanding of the alterations occurring in the fat globules phase during the various treatments in dairy chemistry. As an instance a tentative model is proposed for the copper migration during butter manufacture and the copper content of these butters.