In traditional Shochu making, the fermented mash of the first–stage is generally utilized as the seed of the next first–stage fermentation, which is called Sashimoto. However, with the repetition of Sashimoto, the activity of yeast cells decreases and therefore generally results in bacterial contamination. In this study, a method for activating yeast cells was studied to develop a Shochu making technology by the repetition of Sashimoto for a long–term process. In addition, the yeast stability during the repetition of Sashimoto was studied. Though the trehalose concentration and the activity of yeast cells increased twice after the first Sashimoto, they continued to decrease with the repetition of Sashimoto. However, the yeast cells were successfully activated by shaking the first–stage fermented mash for 10h and the activity of yeast cells remained high during the entire test period. As a result, the ethanol concentration of the second–stage fermented mash improved to more than 18%(v/v). Comparing the flavor compounds of Shochu produced by the repetition of Sashimoto with those of the conventional method, no obvious difference was found in the concentrations of the low–, middle– and high–boiling flavor compounds, nor in the concentrations of isoamyl acetate and β–phenethyl acetate, which are desired flavor compounds. The yeast strain seemed to be stable during the repetition of Sashimoto, according to the results of the nucleotide sequence analysis of NTS regions.
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