Soy protein/β-glucan/tannic acid complex coacervates with different micro-structures play key roles in the rheological properties, tribological properties, and the storage stability of Pickering high internal phase emulsions

Abstract

Soy protein-glucan-tannic acid (S-G-T) complex coacervates were prepared by high-intensity ultrasonic processing (US), subcritical water (SW) treatment, and microfluidization homogenization with different pressures (DHPM 500 and 1000) to stabilize Pickering high internal phase emulsions (HIPEs). Our results show that different treatments affect the microstructure and interfacial properties of ternary coacervates by modifying the intermolecular associations between components. In particular, US and DHPM 500 resulted in the formation of ternary complexes with smaller particle sizes and compact network structures. These properties facilitate the capture of oil droplets. S-G-T (US)- and S-G-T (DHPM500)-stabilized HIPEs exhibit gel-like structures, good creaming stability, and high friction coefficients due to the formation of a three-dimensional network in the continuous phase. However, a more uniform droplet distribution, higher viscoelasticity, and reduced friction were observed after storage for 60 days. These results provide a strategy to improve the sensory characteristics of emulsion-based foods after processing.