PROTEOSE-PEPTONE FRACTION OF BOVINE MILK - DISTRIBUTION IN PROTEIN SYSTEM

Proteose-peptone preparations were isolated from both unheated (95 C for 30 min) skimmilk and from thrice-washed casein micelles. Preparations obtained from both the heated and unheated skimmilk contained three principal components, i.e., serum Components 3, 5, and 8. The preparations obtained from micellar casein did not contain Components 3. Thus, Component 3 appears to be a serum component, possibly of blood origin; whereas, Components 5 and 8, which seem to exist in equilibria between micellar casein and the serum, might be minor caseins. In starch-urea gels, Components 3 and 8 move as single electrophoretic zones, whereas Component 5 migrates as a doublet. © 1969, American Dairy Science Association. All rights reserved.