Technological exploration and antioxidant activity determination of purple compound fruit wine

When it comes to processing, purple pepper and purple corn are poorly utilised even though they are rich in anthocyanins and other nutrients. Therefore, studies focusing on their processing are vital for resolving their underutilisation. In the present work, purple pepper and corn were used to prepare a compound fruit wine. The fermentation process parameters were optimised using single factor tests and response surface design. The sensory characteristics of the compound fruit wine were used as an indicator. The antioxidant potential of the purple compound fruit wine was also assessed using 1,1-diphenyl-2-picrylhydrazyl radical (DPPH·) and hydroxyl radical (·OH) scavenging rates. A purple compound fruit wine with a sensory score of 94.2 and 8.6% alcohol by volume was obtained using a combination of 72.0% purple pepper juice and 28.0% purple corn juice (with an initial sugar content of 23.3%), followed by inoculation with 6.2% Saccharomyces cerevisiae and fermentation for 7.8 d at 23°C. The resulting purple compound fruit wine had a typical harmonious fruit aroma and a mellow taste. Furthermore, the content of anthocyanins in purple compound fruit wine was 1.38 ± 0.14 mg/mL, and the half inhibitory concentration (IC50) values against DPPH· and ·OH were 51.31 and 49.08 mg/mL, respectively. This optimised fermentation process could serve as a theoretical basis for the industrial utilisation of purple pepper and corn.