Pickering emulsions stabilized by rice bran protein particles-glycyrrhizic acid complexes: structural characterization, stability assessment, and curcumin delivery performance.

Abstract

Pickering emulsions (PEs) based on plant proteins commonly suffer from weak interfacial integrity and insufficient stability. This study aims to evaluate the feasibility of using glycyrrhizic acid (GA)-modulated rice bran protein particles (RBPPs)-based PEs for curcumin (Cur) delivery. GA was selected due to its ability to self-assemble into a three-dimensional gel network. RBPPs-GA complexes were prepared at GA concentrations of 0-50%. At 50% GA, the PEs exhibited the smallest droplet size, the highest storage modulus, and superior stability. At a Cur concentration of 1.0 mg/mL, the highest encapsulation efficiency (86.80%) and the minimum droplet size were achieved. In vitro digestion showed that Cur bioaccessibility increased from 53.54% (Cur in oil) to 70.65%, and digestive stability from 65.13% to 75.29%. Overall, RBPPs-GA-based PEs enhanced the in vitro bioaccessibility of Cur and demonstrated rheological properties suitable for 3D printing, making them an effective platform for hydrophobic bioactive delivery and additive manufacturing.