Microwave irradiation: Effect of 8-glucosidase activity by modulating its structural properties in grape maceration stage

In this paper, microwave as an auxiliary method could activate the 8-glucosidase (8 -GC) activity in grape maceration stage. 8 -GC had higher tolerance to acid and temperature during winemaking process. Microwave parameters were optimized for using response surface methodology (RSM), variables including microwave power, temperature, and time. The results demonstrated that the regression equation obtained by using the quadratic regression orthogonal model could better simulate actual operating conditions, the 8 -GC activity increased by 12.54% under optimum conditions (700 W, 48 degrees C, and 6.9 min) comparing to the untreated 8 -GC. The changes in 8 -GC structural properties confirmed that microwave irradiation did increase 8 -GC activity by affecting 8 -GC's side chain group, hydrolysis degree, microenvironment, stability, composition, and conformation. The study would contribute to understanding the mechanism of aroma enhancement by microwave maceration.