Influence of whey protein hydrolysate on surface- active and foaming properties of curd whey

The surface-active and foaming properties of systems containing 100 cm3 of curd whey and from 1 to 3 g of milk whey protein hydrolysate with a degree of hydrolysis of 60 % were studied. The control was whey samples without hydrolysate. The mass fractions of protein, fat, lactose and solids, active acidity, viscosity and surface tension of the samples were studied by instrument methods. The parameters of serum foaming with hydrolysate were studied by whipping 100 cm3 samples at a speed of 10,000 rpm for 10 seconds in a cylinder. When adding hydrolysate, a tendency was observed to decrease the active acidity and increase the viscosity of the whey without a noticeable change in the surface tension of the prototypes. The addition of up to 3 % hydrolysate of whey proteins to the curd whey of a deep degree of hydrolysis of peptide bonds (60 %) had a positive effect on the surfactant and foaming properties of the serum. The observed effects are primarily due to an increase in the mass fraction of whey proteins that perform the function of surfactants in these systems.