Effect of grape indigenous Saccharomyces cerevisiae strains on Montepulciano d'Abruzzo red wine quality

The growth of selected, indigenous Saccharomyces cerevisiae added as starters (SRS1, MS72 and RT73) was monitored during Montepulciano d'Abruzzo wine production. In all the fermentations the addition of the starter, caused a decrease of the non-Saccharomyces yeasts. When strains MS72 and RT73 were used as starters they were detected in the first phases of fermentations, while strain SRS1 competed successfully with native yeasts during all the process. Wines obtained by fermentation with the indigenous starters showed some different characteristics, according to the chemical and sensory analyses. This study highlighted that among selected starters with high fermentative capacity, some are able to dominate better than other natural wine yeast biota, whereas some strains can interact and survive besides native yeast populations during the fermentation. As a consequence, the dominance character can have a positive or negative effect on wine quality and has to be considered in the frame of yeast selection in order to improve or characterize traditional wines. Winemakers could choose among different degrees of yeast dominance to modulate the interaction among starter and native wine yeast population.