The presence of microvilli and other membrane fragments in the non-fat phase of bovine milk

Summary An electron microscopic study of a lipoprotein fraction isolated by ultracentrifugation from skim milk has shown that it is composed of membrane. It is believed that the majority of this membrane arises from shed microvilli. The microvilli may be derived from excess Golgi membrane which accumulates as plasma membrane during the secretion of milk proteins from the mammary cell. These findings indicate that milk may serve as a physiological source of easily isolated membrane. Authorized for publication on July 28, 1971 as paper no. 4025 in the Journal Series of the Pennsylvania Agricultural Experiment Station.