Gelation of casein-whey mixtures: effects of heating whey proteins alone or in the presence of casein micelles

The aim of the present work was to investigate the role of whey protein den aturation on the acid induced gelation of casein. This Was studied by deter mining the effect of whey protein denaturation both in the presence and abs ence of casein micelles. The study showed that milk gelation kinetics and g el properties are greatly influenced by the heat treatment sequence.. When the whey proteins are denatured separately and subsequently added to casein micelles, acid-induced gelation occurs more rapidly and leads to gels with a more particulated microstructure than gels made from co-heated systems. The gels resulting from heat-treatment of a mixture of pre-denatured Whey p rotein with casein micelles are heterogeneous in nature due to particulates formed from casein micelles which are complexed with denatured whey protei ns and also from separate Whey protein aggregates. Whey proteins thus offer an opportunity not only to control casein gelation but also to control the level of syneresis, which can occur.