Stability and in vitro digestion property of lycopene-loaded pickering emulsions stabilized by a novel pea protein isolate nanoparticle-arabic gum-gallic acid ternary complex system.

A novel pea protein isolate nanoparticle-gum arabic-gallic acid (PPINs-AG-GA) ternary particle system was developed as a Pickering stabilizer for lycopene delivery. The effects of gallic acid (GA) concentration and oil volume fraction on particle structure, interfacial assembly, emulsion stability, and digestive behavior were systematically investigated. FTIR, fluorescence spectroscopy, and DSC demonstrated that GA enhanced hydrogen bonding, induced protein conformational rearrangement, strengthened intermolecular interactions, and improved thermal stability. At 0.25 mg/mL GA, Pickering emulsions exhibited the smallest droplet size (44.2 μm), highest interfacial adsorption efficiency (78.2%), encapsulation efficiency (96.7%), viscoelasticity, and thermal stability. Increasing the oil volume fraction (φ = 0.1-0.6) strengthened the gel network and enhanced emulsion stability. Although encapsulation improved lycopene bioaccessibility compared with bulk oil, higher GA concentrations or oil volume fractions suppressed lipid digestion and mixed micelle formation, reducing bioaccessibility. These findings provide a theoretical basis for designing protein-polysaccharide-polyphenol Pickering stabilizers for lipophilic bioactive delivery.