Optimization of Fermentation Process of Grape Medicine Mulberry Wine and Its Antioxidant and Bile Acid Binding Capacity in Vitro

In order to improve the preservation rate of total phenols and flavonoids, the fermentation technology of grape medicine mulberry wine was explored, and the antioxidant activity and bile acid binding capacity of grape medicine mulberry wine were studied. Using grape and medicine mulberry as raw materials, the optimal fermentation process of grape medicine mulberry wine was determined by single factor (inoculation amount, temperature, time, mass ratio) combined with response test. Three antioxidant systems (DPPH·, ABTS⁺·, ·OH) were used to evaluate the antioxidant activity of grape medicine mulberry wine, and the binding ability of different concentrations of grape medicine mulberry wine with glycocholic acid and taurocholate was used to evaluate the effect of reducing blood lipid in vitro. The results showed that the optimum technological parameters of grape medicine mulberry fermentation were: Inoculation amount 0.3%, main fermentation time 8 d, fermentation temperature 26 ℃, raw material ratio 1:3. When the volume concentration of grape medicine mulberry wine fermented by this process was 1.0 mL/mL, the scavenging rates for DPPH, ABTS and hydroxyl radicals were 98.83%, 98.38%, and 99.24%, respectively. It showed that it had stronger antioxidant activity compared with similar fruit wines. When the concentration of grape medicine mulberry wine reached 1.0 mL/mL, the binding rate of grape medicine mulberry wine with glycocholic acid and taurocholate reached 69.36% and 73.28% respectively. It was preliminarily confirmed that the grape medicine mulberry wine had better lipid lowering activity in vitro.