Enhancement of transglutaminase-induced protein cross-linking by preheat treatment of cows' milk: a statistical approach.

摘要

Optimization of heat treated milk towards protein cross-linking induced by transglutaminase was carried out. Capillary electrophoresis was employed to study the extent of cross-linking under different preheating temperatures (70-90 degrees C) and times (15-60 min). The experiments were arranged according to a central composite statistical design (32+centre points). Response surface methodology was used to assess factor interactions and empirical models regarding relative peak area (%) of individual protein ( alpha s2-casein, alpha s1-casein, alpha s0-casein, kappa -casein, beta -casein A1, beta -casein A2, alpha -lactalbumin and beta -lactoglobulin) and total alpha s-caseins, total beta -caseins and whey proteins (sum of alpha -lactalbumin and beta -lactoglobulin). Multi-response optimization was also performed on the total alpha s-caseins, total beta -caseins, kappa -casein and whey proteins data set of the factorial design. The desirability function was the statistical tool employed in this multi-optimization step. The optimum preheating conditions that maximized the cross-linking reactions catalyzed by transglutaminase were achieved within 60 min at 84.5 degrees C..