Yeast Strains Spontaneously Appeared in Sake-mash using Yamahaimoto with no Yeast Addition (II)

摘要

All the isolated strains from the sake-mash using yamahaimoto were sake yeast. Comparedwith the previous study, there were several notable changes in the isolated yeast strains. These included a far greater number of strains capable of growth in potassium-deficient culture media and the lack of nicotinic acid-dependent strains. The interval between the previous study and the current one is 30 years, and the Great Hanshin-Awaji Earthquake can be considered a major cause of the changes in the yeast strains. In the previous study, the isolated sake yeasts had been used for many years at each brewery, while those of the current study were derived from the breweries rebuilt after the destruction by earthquake. Therefore, although some of the original equipment is reused in the new breweries, yeast-flora in produced sake was replaced with the environmental changes.