Effect of glutathione-enriched inactive dry yeast on color, phenolic compounds, and antioxidant activity of kiwi wine

Fresh Xuxiang kiwifruit juice with or without pomace was used for fermentation with different levels of glutathione-enriched inactive dry yeast (g-IDY). After alcohol fermentation, the glutathione (GSH) content, color parameters, phenolic composition, and antioxidant activities of kiwi wine were determined. The results suggested that the addition of g-IDY to kiwi juice increased GSH, glutathione disulfide, total GSH concentrations, and the total phenolic content of kiwi wine. No obvious effect on individual phenolic content was found in wine with g-IDY. The color parameters of wines fermented with pomace were remarkably improved with addition of 100 mg/L and 300 mg/L g-IDY. The supply of g-IDY improved the antioxidant activities of kiwi wine fermented with pomace. Principal component analysis suggested that with the same supplies of g-IDY, wine fermented with pomace was better than wine fermented through pure juice in all measurements. Practical applications: The improvements in color and antioxidant capacity of kiwi wine have always been the focus of kiwi wine brewing. Constant improvement in methods which contribute to high quality of kiwi wine provides crucial support for wine industry and even agriculture development. The aim of this study is to investigate the impacts of glutathione-enriched inactive dry yeast (g-IDY) on quality of kiwi wine. These results could provide feasible advices about g-IDY application to kiwi wine for improving the sensory and nutritional properties. © 2019 Wiley Periodicals, Inc.