Determination of Heat-Induced Lactose-Protein Combination in Milk with Lactose-1-C14

Abstract
A tracer study with lactose-1-C14 indicated how much lactose in cow''s milk combined with the protein fraction on heating. The protein fraction of raw skimmilk contained 0.03% of the added tracer. Heating the dosed skimmilk at 145 and 208 F for 30 min. resulted in 0.06 and 0.7% of added tracer in the protein fraction. These values, represented the percentages of lactose, either in the form of intact lactose or radioactive fragments combined with the protein as a result of heat treatments. A protein-lactose interaction to form a stable complex resulted.