The structural and functional properties changing of peanut protein isolate (PPI) via different treatments and their application in pork meatballs production

Abstract

Herein, the effects of pretreatment methods, such as ultrasound, enzymatic hydrolysis, and their cotreatment methods on the changes in structural and functional properties of peanut protein isolate (PPI) were investigated. The cotreatment method decreased the particle size, molecular weight, surface hydrophobicity, and order extent; moreover, the hydrophobic amino acids and secondary structure of PPI also changed during the cotreatment. Simultaneously, the cotreatment method positively affected the functional properties of PPI. Notably, the solubility could be greatly increased to 88% at pH 5 via ultrasound-papain (U–P) treatment, whereas emulsifying activity was improved to 143.97 m2/g via ultrasound-neutrase (U–N) treatment. Moreover, foaming capacity increased to 65% via U–P treatment, showing that the cotreatment method substantially improved the functional properties of PPI. Pork meatball preparation was used to further investigate the practical application of cotreated PPI. The results indicated that pork meatballs with ultrasound-alcalase (U-A) addition (PMU-A) and ultrasound-protamex (U–Pr) addition (PMU-Pr) exhibited better acceptance in terms of color, tissue status, and overall acceptability compared with control meatballs, indicating that the cotreated PPI has great potential in pork meatball production and can serve as a reference for PPI commercialization.