Thermally stabilised whey protein-pectin complexes modulate the thermodynamic incompatibility in hydrocolloid matrixes: A feasibility-study on sensory and rheological characteristics in dairy desserts

This study investigated thermally stabilised whey protein-pectin complexes (WPPC) regarding their potential as fat-replacer. Sensory and rheological characteristics of WPPC in dairy based desserts were studied using generic descriptive analysis and rotative and oscillatory rheometry. The aroma profile of WPPC was dominated by dairy associated attributes, whereas textural attributes similar to high-fat products were achieved. Attribute intensities increased proportionally with WPPC concentration, enabling a tailoring of sensory parameters. Addition in suspensions and vanilla sauces revealed that WPPC acted as non-interactive fat-replacers, reaching apparent viscosities similar to products rich in fat. In solid gelled puddings, a slight softening of the gel was found which was attributed to thermodynamic incompatibility between unbound pectin and the embedding starch matrix. Based on this, a model for the modes of action of WPPC depending on the matrix - requirements was postulated stressing the role of pectins as thickeners in liquid and semi-solid systems and of excluded volume effects in solid gels.