Abstract
To produce a characteristic craft beer, a flavor-producing wild yeast was isolated using an enriched culture method from tree sap collected from the Ise-shima area. A comparative analysis of the sequences of ITS1-5.8S rDNA-ITS2 region indicated that the isolated strain was related to Saccharomyces cerevisiae and was named KADOYA1. To evaluate the characteristic and utility of KADOYA1, a commercial scale (1,000 L) of beer production test was performed using ale beer yeast strains 1056 and 3068 as a control. The fermentation rate of KADOYA1 was slightly lower than that of strains 1056 and 3068, but ethanol production was sufficient. The odor properties of beer brewed with each yeast strain were estimated by gas chromatography-mass spectrometry, and a fragrance evaluation was performed using an electronic noses (FF-2A). The results showed that the beer brewed with KADOYA1 has a characteristic odor that is different from that of the beers brewed with the other two strains. KADOYA1 was deemed to be a commercially useful yeast for craft beer production because it has sufficient fermentation and good flavor-producing abilities. KADOYA1 is expected to be used to produce craft beer with a unique flavor.
