Effects of ultrasound pretreatment on the enzymolysis of hybrid sturgeon (Huso dauricus x Acipenser schrenckii) protein and the structural, functional, and antioxidant properties of hydrolysates

In the current study, hybrid sturgeon hydrolysates were prepared using ultrasound (US) pretreatments for different periods (0, 15, 30, and 45 min) followed by an enzymolysis process using compound proteinase, and their structural, functional, and antioxidant properties were examined. The application of US pretreatments significantly increased the hydrolysis process. SDS-PAGE analysis revealed that as sonication time was increased, peptides with lower molecular weights were obtained. Based on US pretreatment time, hydrolysates demonstrated significant changes in free amino acids, solubility, emulsifying properties, surface hydrophobicity, and water-oil holding ability. Furthermore, US pretreatments had a significant impact on the antiradical activity (DPPH center dot and ABTS center dot+) at different hydrolysate concentrations. Partial least-squares regression (PLSR) analysis revealed a positive relationship between most hydrolysate properties and the degree of hydrolysis. These findings indicated that using US pretreatments would be a promising procedure for improving the functional, structural, and antioxidant properties of hybrid sturgeon hydrolysates, thereby expanding their application in the field of food processing.