Interfacial regulation of ball-milled modified Gorgon Euryale starch complexed with xanthan gum and stabilization mechanism of Pickering emulsions

Abstract

Ball milling treatment, which can physically modify starch granules as an environmentally friendly and effective mechanical technology, has emerged as a versatile method to prepare natural biopolymer-based emulsion systems in food industry. Hence, the interfacial behavior of ball-milled modified starch complexed with other plant-based polysaccharide emulsifiers and stabilization mechanism of formed Pickering emulsions are worthy of further study. In this work, the structural remodeling of Gorgon Euryale starch (GES) induced by ball milling and the stabilization mechanism of Pickering emulsions co-constructed with xanthan gum (XG) were investigated. Scanning electron microscopy (SEM) analyses revealed that ball milling significantly remodeled GES granules. Fourier transform infrared (FTIR) spectra showed that ball milling reinforced the interactions between GES and XG, and the interfacial wettability and emulsion stability were improved significantly. Furthermore, Pickering emulsions were fabricated by compounding ball-milled GES with XG. Analyses using optical microscopy, nanoparticle size analyzer, rheometer, and texture analyzer showed that the synergistic effect of ball-milled GES and XG could significantly reduce the droplet size of emulsions, improve the emulsification index, and enhance shear stress, apparent viscosity, and textural properties. The GES-XG emulsion system showed the characteristic of anti-delamination, with the E195/5 emulsion maintaining uniformity over 14 days. Ball-milled GES formed a physical barrier at the oil-water interface, while XG stabilized through interfacial composite films and increased aqueous viscosity. This work provides new insights for preparing natural polysaccharide-based Pickering emulsions.