• Korean Journal of Microbiology
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• v.52 no.1
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• pp.98-109
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• 2016

The study was aimed to investigate the mixing ratio of kiwi and persimmon juices for the production of good quality wine by Saccharomyces cerevisiae Y28. Firstly, the optimum condition of rapidase treatment for the kiwi and persimmon juices was established, thereafter various mixing ratio (10:0, 9:1, 8:2, 7:3, 6:4, 5:5) of kiwi and persimmon was investigated regarding physiochemical properties and flavor compounds of wine. As the result, the optimum conditions were obtained as 0.3% rapidase for 1 h in kiwi and 0.3% rapidase for 3 h in persimmon. According to higher ration of persimmon, the pH of wines increased from 3.69 to 3.77, while the acidity of wines decreased from 2.07% to 1.51% at 14 days fermentation. The ranges of brix and reducing sugar in wines were decreased which ranges around 9.6 to 8.8 and 6.07 to 6.90 g/L, respectively, after fermentation. Major organic acid in wines were identified as tartaric acid, malic acid, and citric acid. A small amount of free sugar such as sucrose and glucose were detected in wines, but fructose was completely absent. The soluble phenolic contents were decreased that ranges around 1.00 to 1.25 g/L, in contrast, browning degree were increased ranges around 0.212 to 0.412 after fermentation. The major flavor components were identified as ethyl acetate and hydrazine, and 1,1-dimethyl. Importantly, phenylethyl alcohol was detected from the all wines that have a typical rose like flavor. But sensory test results and preference of kiwi-persimmon (7:3) mixing wine was better than the other wines.

• Food Science and Preservation
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• v.30 no.1
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• pp.52-64
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• 2023

100 different yeast colonies were isolated from spontaneously fermented kiwis, persimmons, apples, pears, watermelons, grapes, grape fruits, peachs, and plums, and selected yeast strains were used to produce kiwi-persimmon mixed wine (KPMW). Among the isolates, five representative strains exhibited tolerance to sucrose, alcohol, pH, and potassium metabisulfite when compared with the control yeast strain (Saccharomyces cerevisiae KCCM 12615). All five yeast strains (Y4, Y10, Y28, Y78, and Y81) exhibited 99% 26S rDNA sequence similarity to S. cerevisiae. The pH, acidity, Brix, reducing sugar, alcohol, and organic acid contents were consistent in KPMW prepared from the S. cerevisiae KCCM 12615 and Y28 strains. KPMW made from the Y4, Y10, and Y28 strains exhibited lower quantities of free sugars than those of the KPMW made from the other yeast strains. The level of ethyl esters in KPMW prepared from the Y28 was higher than that in the other KPMWs. All strains, except for Y28, produced lower concentrations of sulfur and ketone compounds. Furthermore, the KPMW produced by the Y28 strains had total phenolic contents with 1.1 g/L, with DPPH and ABTS radical scavenging activities of 57.06% and 55.62%, respectively, and a FRAP assay value of 0.72. Our results suggest that Y28 is a promising yeast strain for producing high-quality wines.