Effect of calcium chloride and moderate shear on β-lactoglobulin aggregation in processing-like conditions

The influence of two variables (moderate shear and calcium chloride concentration) on the properties of β-lactoglobulin (β-lg) aggregate suspensions obtained by dynamic heat treatment (85 °C for 60 s) was studied. Variations in calcium chloride concentration from 5.1 to 7.1 mM were imposed, and led to major changes in the aggregate properties. The characterization of the aggregate size was performed using three distinct methods: laser granulometer, dynamic light scattering (DLS) and focus beam reflectance measurement (FBRM). Viscosity and residual native fraction were also determined. Statistical analysis of experimental data underlines the important combined effect of the two variables and paves the way for new ways of controlling the aggregate functionalities. The calcium chloride concentration has an effect on the entire aggregation process, from native β-lg to large aggregates. On the other hand, shear only impacts the formation of the large aggregates.