Work

Effects of thermal and mechanical processing on the properties of protein structures in dairy systems with tailored composition

Year: 2026

Type: article

Abstract: The study aimed to evaluate how various thermal and mechanical processing conditions affect the state and properties of colloidal particles in skim milk concentrates (15% and 20% total solids) obtained via membrane and vacuum concentration methods. Thermal processing above 85°C was established to enlarge colloidal particles through whey protein denaturation and aggregation with casein micelles, modifying the rheological, structuralmechanical, and technological properties of dairy systems based on skim milk concentrates and resulting fermented products. Homogenization at 20 MPa did not significantly affect whey protein denaturation but decreased protein particle size, thereby reducing concentrate viscosity post-homogenization; this reduction remained stable during subsequent pasteurization. This effect can be attributed to the compression of casein micelles in the concentrates during homogenization, leading to their partial dissociation and the migration of certain fractions from the colloidal phase into the whey. The study confirms that optimal milk concentrate processing conditions (95°C for 5 minutes with preliminary homogenization at 20 MPa) achieve the required structural-mechanical properties of the resulting systems while ensuring superior functional properties and final product stability.

Source: Proceedings of universities Applied chemistry and biotechnology

DOI: 10.21285/achb.1046