The Folate Binding in Milk

Abstract

The free-folic acid activity of milk appears to be bound to a protein. The binding seems to be highly specific, as it is not broken by autoclaving. Synthetic PGA, but not 4-amino-10-methyl PGA, is able to bind to milk. This binding seems to be semispecific only, the bond being broken by autoclaving. Two types of vitamin B₁₂ binding also appear to be present in milk. Autoclaved milk may be deprived completely of its free folic acid activity but only partially of its vitamin B₁₂ activity through adsorption with activated charcoal.