Influence of pH on the dry heat-induced denaturation/aggregation of whey proteins
Résumé
The effect of pH on the heat-induced denaturation/aggregation of whey protein isolate (WPI) in the dry state was investigated. WPI powders at different pH values (6.5, 4.5, and 2.5) and controlled water activity (0.23) were dry heated at 100 degrees C for up to 24 h. Dry heating was accompanied by a loss of soluble proteins (native-like beta-lactoglobulin and alpha-lactalbumin) and the concomitant formation of aggregated structures that increased in size as the pH increased. The loss of soluble proteins was less when the pH of the WPI was 2.5