Construction of high internal phase Pickering emulsion using dual protein hydrolysates-naringenin supramolecules and their contribution on curcumin bioaccessibility

Abstract

The potential of dual protein–polyphenol supramolecular complexes for constructing delivery systems based on high internal phase Pickering emulsions (HIPPEs) is significant, yet the underlying mechanism has not been fully revealed. This study systematically investigated hybrid supramolecular complexes fabricated through physical processing techniques such as ultrasound (US) and high pressure (HP), integrating sunflower-walnut protein hydrolysates (SW) with naringenin (Nar) as novel stabilizers for oil-in-water HIPPEs. While physical treatments effectively enhanced SW emulsification capacity through particle size reduction, interfacial tension decrease, and wettability increase, particularly under US treatment, the physical field (US and HP) has limited effectiveness in improving the emulsion’s cream stability. The synergistic application of physical processing and naringenin complexation induced SW structural unfolding, facilitating the adsorption and anchoring of SW at the oil–water interface. Compared to the SW-Nar (US), SW-Nar (HP) generated emulsions with smaller droplets, reinforced viscoelastic networks, and improved curcumin bioaccessibility. In vitro digestion induced SW-Nar complexes interfacial structural unfolding, hydrophobic exposure, and α-helix-to-β-sheet transition, enhancing emulsification and micelle formation via strengthened hydrogen bonds and hydrophobic interactions, particularly in SW-Nar (HP). These findings collectively establish SW-Nar-stabilized HIPPEs as advanced delivery platforms for lipophilic bioactives, with system performance critically dependent on supramolecular interfacial microstructure modulated by physical processing methods.