Cycloheximide resistance as marker for monitoring yeasts in wine fermentations

When selected yeast strains are used in wine-making, it is necessary to ensure that the fermentation process is really conducted by the inoculated yeast. Saccharomyces cerevisiae spontaneous mutants resistant to cycloheximide (cyh(r)) were isolated from industrial strains. The mutations did not affect the fermentation kinetics the quality of the wines, or the viability of active dry yeast made with the mutants. By using these mutants, we developed a fast, reliable, and economic method to monitor inoculated selected yeast through must fermentation. The method can be recommended to the food industry because it is simple, and does not require sophisticated equipment or special personnel skills. We used this method to confirm the dominance of the inoculated selected mutants during grape juice fermentation. (C) 2000 Academic Press.