Identification and technological characteristics of yeast strains from vineyards in Slovakia

Slovakia, a central European country, has a long lasting tradition of vine growing and producing wine, where yeasts significance in winemaking process and their region- and climate-depending specificity lies in the centre of research interest. In this study, yeast consortium profiles of several vineyards and vine varieties in four following years were identified and confirmed by biochemical tests. Pure yeast cultures were obtained from grapes, must, fermenting must and young wines. Isolated genera such as Saccharomyces, Kloeckera, Candida, Rhodotorula or Lachancea were placed in the wine yeast collection. Significant technological properties of identified yeast strains (ethanoltolerance, osmotolerance and thermotolerance) were studied. All strains isolated from variety Sauvignon Blanc harvested in all four investigated years showed high ethanol- and osmotolerance. Two Kloeckera apiculata strains from variety Blaufränkisch (year 2017) were osmotolerant, identically with K. apiculata isolated from the Green Veltliner in the same year. Four Saccharomyces cerevisiae strains isolated in 2017 from White Riesling showed high ethanoltolerance and osmotolerance.