Viscoelastic properties of whey protein concentrate gels with honey and flour at different pH

Abstract

Viscoelasticity of heat induced gels from whey protein concentrate, with different contents of honey and wheat flour, and prepared at pH 3.75, 4.2 and 7.0, was studied by using dynamic rheological assays. The elastic modulus of gels prepared at neutral pH was higher than the corresponding to acidic gels, probably due to the fact that sulphydryl-disulfide interchange reactions are favoured at neutral pH. Honey decreased the elastic modulus and increased the viscous modulus and the complex viscosity in all conditions assayed. Wheat flour increased the elastic modulus, and all samples exhibited a gel-type behaviour except at high honey content.