Expression of 2 Lipomyces kononenkoaeα-Amylase Genes in Selected Whisky Yeast Strains

Nineteen whisky yeasts were evaluated according to their fermentation performance and ability to produce a palatable spirit. Four of these strains were selected and, together with a commercial wine yeast strain (control), were transformed with integration plasmids containing the LKA1 and LKA2 α‐amylase genes from the yeast Lipomyces kononenkoae. Fermentation trials with starch‐containing media indicated that the transformants produced between 47% and 66% of the theoretical ethanol yield. This study has resulted in progress toward the development of whisky yeast that could ultimately be used in a process during which production of amylases, hydrolysis of starch, and fermentation of resulting sugars to grain whisky occur in a single step.