Abstract
Although “regional microorganisms” are often used in the food industry, such as in sake brewing, there are no reports comparing the characteristics of products obtained using wild and bred microorganisms. The aim of the present study was to evaluate the potential of applying a wild microorganism to Sake brewing. Four strains of Saccharomyces cerevisiae were isolated from the soil in Shikoku Island, Japan. Sake was brewed using these 4 wild-type strains and Sake yeast kyokai No. 7, and the resulting products were analyzed and compared. The Sake meter value (SMV) of the Sake brewed using kyokai No. 7 was +10. In contrast, the SMV of the Sake brewed using the wild strains were from －9.7 to －19.2. Additionally, Sake brewed using the wild yeasts had lower concentration of isoamyl acetate and higher concentration of acetic acid than Sake brewed using kyokai No. 7. The antioxidant activity of Sake was determined as the capacity to reduce copper ion and scavenge free radicals. The antioxidant activity of Sake was weaker than that of red wine and stronger than that of white wine. All wild isolates could be applied to brewing Sake. Sake brewed by wild yeasts had distinguishing organic acid composition. Development of novel brewing methods and breeding of wild yeasts will promote wider application of “regional yeasts.”
