In cream suspensions and partly skimmed milks obtained by successive centrifugation from whole milk, the concentration of vitamin A per gram of fat was inversely related to the mean size of fat globules. This result indicated that not all the vitamin A of milk was located in the fat globule core, which was further supported by studies of buttermilk and butter oil fractions obtained by churning of cream. These studies indicated that a portion of the vitamin A was associated with the fat globule membrane. The vitamin A content per gram of fat of purified fat globules was similar to vitamin A content per gram of fat of the whole milk from which they were isolated. This result indicated that the amount of vitamin A in the serum fraction was negligible and that vitamin A was localized in the fat globule and fat globule membrane.
Bibliographical noteFunding Information:
Received November 17, 1993. Accepted November 7, 1994. lhblished as Paper Number 19558 of the contribution series of the Minnesota Agricultural Experiment Station based on research conducted under Project 18-24, supported by University of Minnesota Computer Center and National Dairy Promotion and Research Board. 2Present address: Departement de Chimie-Biochimie Alimentaire, Institut Agronomique et Veterinaire Hassan 11. B.P. 6202, Rabat-Instituts, Rabat, Morocco. 3T0 whom correspondence should be addressed.
- distribution, milk
- vitamin A