Insight into the stabilization of Pickering emulsion by modified soybean dietary fiber: Enhancing interaction forces...

This study investigated the effects of steam exploration on soybean insoluble dietary fiber (U-IDF and M-IDF), and characterized the resulting stabilized Pickering emulsion. The particle size, ΔE, and water/oil holding capacity of M-IDF decreased, while its absolute value of zeta potential and contact angle increased. Significant changes in the intensities of the functional groups (-OH and CO) were observed in the Fourier transform infrared (FTIR) spectra of M-IDF. Observation from scanning electron microscopy and atomic force microscopy indicated that the M-IDF exhibited a wrinkled structure and reduced particle size. Pickering emulsions prepared with modified IDF (M-PE) exhibited smaller droplet sizes and higher stability than those with unmodified IDF (U-PE), with optimal stability achieved at 3% M-IDF mass percentage and 20% oil phase volume (MPE-3%/20%). Variable-temperature FTIR analysis revealed that IDF mass percentage has a greater influence on the thermal stability of Pickering emulsions than oil phase volume. The viscosity and modulus (G', G″) of MPE-3%/20% increased due to the formation of a more stable network structure, driven by the inter-particle dispersion forces and electrostatic repulsive forces. MPE-3%/20% also exhibited desirable stability under different environmental conditions and the stabilization mechanism of Pickering emulsion primarily involves electrostatic repulsion and steric hindrance.