Shochu brewing characteristics and properties of a trichothecin-resistant shochu yeast mutant

An antibiotic-resistant strain of Saccharomyces cerevisiae was isolated from shochu yeast. Three mutants were used for shochu brewing and gave higher ethanol productivities than the parent. The mutants were resistant to cycloheximide, cerulenin, trichothecin and other organic compounds such as lauric acid. In the presence of 20% (v/v) ethanol, the viability of the mutants was 87-96%, but that of the parent was 77%. Zymolyase treatment for 3 h, decreased the viability of the parent by 44% but that of the mutants only by 11-32%. Thus the higher ethanol productivity of these mutants is related to their high ethanol tolerance and resistance to various organic compounds.