Ethanol formation by hybrid yeasts

Summary Fusion products between Saccharomyces cerevisiae and Saccharomyces mellis were examined for their fermentative capacity. While there was little difference in the fermentation rate between S. cerevisiae (industrial strain) and the hybrids at low sugar concentrations (4% glucose), at 35% the hybrid strains were far superior (13.6% w.w. vs. 9.0% w.w.). Data on the accumulation of intracellular ethanol seem to indicate that the high fermentation efficiency of the hybrid strains may be due, in addition to their osmotolerance, also to their improved ability to excrete ethanol from their cells.