Improvement and modification of whey protein gel texture using polysaccharides

Whey proteins (WP) and polysaccharides are two gelling biopolymers used in the food industry for their wide range of rheological and textural properti es. Mixed gels containing more than one gelling agent are usually classifie d into three types: interpenetrating, coupled, and phase-separated networks . Large deformation behavior of whey protein gels mixed with polysaccharide s is presented. pH, and the concentration and nature of the cations added i n the system, affect both protein and polysaccharide gels. These factors wi ll also modify the mixing behavior of protein-polysaccharide solutions. The effect of cations and pH are respectively explained using WP/kappa -carrag eenan and WP/pectin systems. Under the conditions studied, two types of mix ed systems were obtained: one with two gelling biopolymers (WP/kappa -carra geenan), and the other where protein is the only gelling biopolymer (WP/pec tin). Conditions favoring incompatibility can lead to spherical inclusions of whey protein. (C) 2001 Elsevier Science Ltd. All rights reserved.