Hydrolyzed rice glutelin assemblies: how interfacial microstructure and rheology contribute to Pickering emulsion stabilization.

Abstract

Pickering emulsions stabilized by protein assemblies have attracted increasing attention. However, how protein architectures regulate interfacial and bulk properties to determine emulsion stability remains unclear. In this study, fibrils, particulates, and amorphous assemblies of hydrolyzed rice glutelin (HRG) were prepared. Their interfacial films were evaluated using dilatational rheology, Lissajous curves, and general stress decomposition, while emulsion rheological properties were characterized by mechanical and micro-rheological measurements. HRG fibrils exhibited faster adsorption (0.72 mN/m/s1/2) and penetration rates (3.03 × 104 s-1), whereas HRG particles showed higher rearrangement rates (9.19 × 104 s-1). HRG fibrils generated the most stable emulsions by forming elastic interfacial films and dense networks, exhibiting enhanced viscoelasticity, as evidenced by higher storage modulus and complex viscosity. These findings reveal the synergistic roles of interfacial microstructure and rheology in protein-based Pickering emulsion stabilization.