DYNAMICS OF THE YEAST-STRAIN POPULATION DURING SPONTANEOUS ALCOHOLIC FERMENTATION DETERMINED BY CHEF GEL-ELECTROPHORESIS

Wine yeasts were isolated from spontaneous alcoholic fermentations per formed with white and red grape musts from vintages 1991 and 1992. Yea st cells were analysed by physiological tests and gel electrophoretic karyotyping. It was shown that there is a succession of different stra ins in the yeast population during the time course of the fermentation process. Furthermore, the composition of the yeast strain population differs from grape must to grape must and from year to year, and may t herefore be considered vineyard (terrain)- and vintage-dependent.