Synergistic dual mechanisms in emulsion stabilization: hierarchical reinforcement via 3D oleogel networks and nanoparticle-engineered interfacial monolayers

Although protein-polysaccharide complexes have been widely explored as Pickering emulsifiers, their cooperative stabilization with oleogels in composite emulsion systems has been rarely investigated. This study constructed whey protein isolate fibril-chitosan (WPIF-CS) nanoparticles via acid-thermal treatment and electrostatic self-assembly technology, and systematically investigated the dual stabilization mechanisms mediated by composite nanoparticles and beeswax-based oleogel matrices in Pickering emulsions. Optimized nanoparticles (3:1 WPIF/CS ratio, pH 5.6) achieved a 62.79 ± 2.40° contact angle with enhanced three-phase equilibrium. Emulsions containing 26 mg/mL beeswax-oleogel and 40 mg/mL nanoparticles showed strong viscoelasticity (G' = 454.71 Pa > G" = 124.63 Pa). The emulsion stability originated from dual structural synergy: the three-dimensional cross-linked network of oleogels provided skeletal support, meanwhile nanoparticle interfacial adsorption formed dense monolayers, with their combined effect achieving multi-level stabilization. The system retained integrity through 14-day storage and three freeze-thaw cycles. This work provides novel strategies for food-grade emulsifiers and deciphers multi-scale oleogel-nanoparticle synergy mechanisms.