Physicochemical characterization and environmental stability of a curcumin-loaded Pickering nanoemulsion using a pea protein isolate-dextran conjugate via the Maillard reaction

This study investigated pea protein isolate (PPI) and dextran (DX) conjugates produced via the Maillard reaction as Pickering stabilizers for various food applications. The results found that as heating time increased (0-5 h), the grafting degree heightened. The PPI-DX conjugate exhibited a rough porous surface in contrast to native PPI, accompanied by changes in molecular weight and secondary structure. Additionally, the aggregation of low-solubility PPI was partially inhibited due to the contribution of increased solubility and reduced surface hydrophobicity by glycation. Curcumin-loaded Pickering nanoemulsions stabilized with PPI-DX had smaller droplets and higher curcumin encapsulation (greater than80 %) than PPI-stabilized nanoemulsions. PPI-DX adsorbed on the interface showed improved physical stability compared to PPI alone, even after various pH conditions and three heat treatments. The nanoemulsion stabilized with PPI-DX demonstrated improved apparent viscosity and dispersion stability. These findings highlight the effectiveness of PPI-DX conjugates as stabilizers for developing stable and functional Pickering nanoemulsions.