Yeast Population Dynamics during the Fermentation and Biological Aging of Sherry Wines

ABSTRACTMolecular and physiological analyses were used to study the evolution of the yeast population, from alcoholic fermentation to biological aging in the process of “fino” sherry wine making. The four races of “flor”Saccharomyces cerevisiae (beticus, cheresiensis, montuliensis, androuxii) exhibited identical restriction patterns for the region spanning the internal transcribed spacers 1 and 2 (ITS-1 and ITS-2) and the 5.8S rRNA gene, but this pattern was different, from those exhibited by non-florS. cerevisiaestrains. This flor-specific pattern was detected only after wines were fortified, never during alcoholic fermentation, and all the strains isolated from the velum exhibited the typ…