Small Angle X-Ray Scattering Studies on the Effects of Ultra Shear Technology on Model Animal and Plant-Based Protein Solutions

Abstract

The effects of shear, temperature, and high pressure on model solutions of bovine milk and plant proteins were investigated. Samples of bovine β-lactoglobulin (BLG), pea lectin (PL), and their mixture (MIX) were treated by high-pressure processing (HPP) and ultra-shear technology (UST). BLG and PL are known for their allergenic properties, and processing conditions can potentially be used to decrease allergenicity, as well as engineer beverage properties of interest. Small angle X-ray scattering (SAXS) and confocal laser scanning microscopy were used to measure the impact of processing on the protein solutions from the microscopic to the molecular scale. SAXS data were analyzed by various approaches to assess changes in protein size and shape, oligomerization, and aggregation. The results are consistent with the BLG sensitivity to shear, pressure, and temperature. The pressure holding time was shown to be critical and thermal effects at ambient pressure are distinct from those observed under pressure. Although some changes in shape were detected, PL showed structural and colloidal resistance to the processing conditions applied. The MIX solutions appear to show a convolution of the effects observed on the isolated protein solutions, granting further investigation to clarify potential interactions between the proteins. These findings are valuable for the development of liquid beverages based on animal and plant proteins and their blends, enhancing control over functional properties and expanding their applications in food, nutraceuticals, and biomedical fields.