Self-assembly of pea peptides prepared by ultrasound-regulated enzymatic hydrolysis

Peptides obtained by enzymatic hydrolysis easily and spontaneously self-assemble in solution. Ultrasound could drive the self-assembly of peptides. Different self-assembly behaviors result in peptides having varied structural and functional properties. Herein, the self-assembly behaviors of ultrasound-regulated enzymatic hydrolysis pea protein hydrolysates (UPPH) and enzymatic hydrolysis pea protein hydrolysates (PPH) were compared. The proportion of the molecular weight below 1 kDa in UPPH was higher than that in PPH, and a lower critical micelle concentration was observed in UPPH. Compared with PPH, higher levels of peptide chain hydrophobic tail ends, β-structures, surface tryptophan, and hydrophobic peptides were observed in UPPH. The results of transmission electron microscopy showed that UPPH self-assembled nanoparticles were loose and had free peptide chains on their periphery. Hydrophobic interactions were the dominant interactions of UPPH. Compared with PPH, UPPH had stronger amphiphilicity and self-assembly capability. This study provides a theoretical basis and data support to expand the application of pea peptides in the food industry.