Effect of the FAA1 Gene Disruption of Sake Yeast on the Accumulation of Ethyl Caproate in Sake Mash

Abstract Fatty acid activation gene ( FAA1 ) in sake yeast Kyokai no. 701 (K701) was disrupted to investigate the accumulation of ethyl caproate in sake mash. Ethyl caproate, recognized as an important apple-like flavor in sake, is generated by fatty acid synthesis in yeast cells. The disruptant for the FAA1 gene (K701Δfaa1) exhibited a reduced growth rate in a medium containing cerulenin and myristic acid or oleic acid compared with that of the parental strain (K701). In a sake brewing test in which the rice used was polished to 60% of its original size, the fermentation ability of K701Δfaa1 was inferior to that of K701 but the production of ethyl caproate by K701Δfaa1 was 1.6-fold higher than that by K701. These results suggest that the FAA1 gene in sake yeast plays an important role in sake brewing and the accumulation of ethyl caproate.