Investigation of wine fermentation of three-leaf cayratia (Cayratia trifolia L.) using Saccharomyces cerevisiae 2.1

Background Cayratia trifolia has been extensively studied for its bioactive components and medicinal properties. This study was carried out to evaluate the fermentation ability of yeast Saccharomyces cerevisiae 2.1 to determine suitable fermentation conditions. Methods The suitable initial sugar content, temperature, and incubation time were investigated in the fermentation in the 100-milliliter flask scale. Besides, a trial fermentation at the 1-liter scale was conducted to assess yeast performance. Results All treatments showed that the total sugar content decreased after 9 days of fermentation compared to the initial level. Temperature during fermentation has a direct effect on yeast activity. Temperature increases the growth of yeast and the speed of enzyme activity. The fermentation time changes depending on temperature, initial soluble solid contents, and yeast strains, leading to changes in the ethanol content after the end of fermentation. The results showed that the S. cerevisiae 2.1 was able to ferment at room temperature with an initial pH of 4.5, 24 °Brix, and a yeast density of 10 ⁷ cells/mL. The appropriate fermentation conditions determined for S. cerevisiae 2.1 were 24 °Brix and incubation at room temperature (28-33°C) with a fermentation time of 11 days. In 1-L scale fermentation, three-leaf cayratia wine had 9.46% (v/v) and the fermentation efficiency was 90.34%. The wine produced had a unique color, flavor, and aroma that met the sensory evaluation of the Vietnamese national standard TCVN-3217:79. Conclusion The results showed that the S. cerevisiae 2.1 was able to produce wine from Cayratia trifolia extract in suitable conditions with high ethanol content and organoleptic values. The results of this study supplied needed information for further studies on analysis of bioactive compounds produced by the fermentation.