Short communication: Presence of galactose and glucose promotes browning of sweet whey powder

This research examined the role of sugar type on the browning of sweet whey powder during accelerated storage. Two model systems, a lactose-lysine system and a sweet whey powder system, were selected. Within each model system experiment were samples containing equimolar concentrations of lactose, galactose, and glucose, and model systems were studied at 3 pH values: 6.5, 6.0, and 5.5. Samples were analyzed for changes in color after accelerated browning at 80 degrees C for 24 h. The results showed that the samples containing galactose and glucose browned to a greater degree than those containing lactose. Browning in the control and lactose-enriched samples was more susceptible to changes in pH. This study indicates that the processing conditions of liquid whey in which the lactose monomers glucose and galactose accumulate may predispose SWP to brown more readily.