Rennet Coagulation of Milk Retentates. 2. The Combined Effect of Heat Treatments and Protein Concentration

Abstract

The aim of this research was to study the clotting kinetics, curd hardening, and whey syneresis of milk concentrated by UF. Experiments were conducted on raw, pasteurized, and UHT-treated milks to verify whether the depression of coagulation characteristics caused by heat treatments of milk could be reversed by the increase in protein concentration. Data demonstrate that rennin action on milk strongly depends on the severity of heat treatment and that curd consistency is influenced both by heat treatment and protein concentration. Ultrafiltration modifies the viscoelastic behavior of curd, resulting in a marked increase in the viscous component at increasing protein concentration. Syneresis decreases as protein concentration increases and is strongly affected by pasteurization and UHT treatment. © 1989, American Dairy Science Association. All rights reserved.