Regulation of protein flexibility and promoting the formation of high internal phase emulsions in peanut protein isolate using dual succinylation and ultrasonication modifications

In order to obtain a high self-supporting capacity protein-based high internal phase emulsions (HIPEs) suitable for food 3D printing, the peanut protein isolate (PPI)-HIPEs was prepared by improving the protein flexibility under dual succinylation and ultrasonication modification. It has been found that the succinylated PPI (PPI-DS) showed decreased particle size, ζ-potential, and surface hydrophobicity, but increased protein flexibility and solubility. Following the succinylation modification, ultrasound induced additional improvements in these characteristics. Of these, the PPI-DS-300 W had the highest performance. The combination of dual succinylation and ultrasonication significantly altered the secondary structure of PPI, disrupting rigid globular structures and enhancing molecular flexibility. The improvement of protein flexibility decreased interfacial tension and strengthened interactions at the protein-oil interface, which further optimized its emulsifying performance. Furthermore, the dual succinylation and ultrasonication modifications generated stronger gel-like network structures to enhance the mechanical strength and deformation resistance of the HIPEs.