Pickering Emulsions Stabilized by Conjugated Zein-Soybean Polysaccharides Nanoparticles: Fabrication, Characterization and Functional Performance

This study aims to fabricate zein-based colloidal nanoparticles, which were used to stabilize Pickering emulsions, by conjugation with soybean polysaccharide (SSPS) through the Maillard reaction. The physicochemical properties of the conjugated particles as well as the physical and oxidative stability of the fabricated Pickering emulsion that utilized conjugated colloidal particles with the volumetric ratio of water and oil at 50:50 were investigated. The grafting degree of zein and SSPS was verified through examination of FT-IR and fluorescence. Moreover, the conjugated Zein/SSPS nanoparticles (ZSP) that were prepared after dry heating for 48–72 h exhibit excellent colloidal stability across a range of pH values (4.0–10.0). Further, the wettability of ZSP decreased based on a contact angle analysis of θ~87°. Confocal laser scanning microscopy (CLSM) images indicated that ZSP particles were located around the oil droplets. Additionally, the ZSP effectively improved the oxidative stability of the Pickering emulsions, as demonstrated by a significant decrease in both peroxide value (PV) and thiobarbituric acid reactive substances (TBARS). The results of this study demonstrate that ZSP represents a promising food-grade Pickering emulsifier, capable of not only stabilizing emulsions but also inhibiting their oil oxidation.