Yeast strains stable at high temperature (40°C) were applied to
shochu making for the purpose of saving energy for processing, shortening of producing period, and improving quality of alcoholic beverages produced. Three hundred strains of yeast were isolated from Luck Pang (Thailand), Chinese
Koji (Yunnan) and so on, and 7 stains of ethanol-producing yeasts stable at high temperature were finally selected after repeated screening. These strains were identified as
Saccharomyces cerevisiae although the strains showed some differences in taxonomic identification. These strains showed higher specific growth rate and shorter generation time than the standard strain of shochu yeast, MK 021, at 30°C and 40°C. These stains gave higher concentration of alcohol than MK 021 at lowpH and high temperature in small scale
shochu mash fermentation test. Pulse field electrophoretic karyotypes of their chromosomal DNA were similar to those of strains MK 021 and 1031 R in their numbers and sizes of chromosomal DNA. However, most of these strains showed partly unique band patterns due to chromosome polymorphisms.
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