Selection and identification of autochthonous yeasts in Slovakian wine samples using a rapid and reliable three-step approach

Aims: The investigation of yeast microflora during the must fermentation of two wine varieties (Frankovka modra - Blaufränkisch and Veltlinske zelene - Grüner Veltliner) from two consecutive vintages was performed using a three-step approach. Methods and Results: The investigation strategy consisted of the combination of yeast cultivation, selection of the isolated yeasts based on the amplification of internal transcribed spacer 2 using a fluorescence-labelled primer (f-ITS-PCR) and a final identification step based on amplification and sequencing of the ITS1-5.8S rDNA-ITS2 region of the selected yeasts. By this three-step approach, it was possible to screen 433 yeasts isolates that belonged to 13 different species. Conclusions: The f-ITS-PCR allowed the unambiguous differentiation of all isolated yeast species that produced their typical f-ITS-PCR profile. Significance and Impact of the Study: This is one of few reports that treat the yeast diversity in Slovakian wines and in two varieties largely cultivated in Central Europe. The three-step approach permitted the rapid and reliable identification of isolated yeasts. The f-ITS-PCR with its good discrimination power can represent a suitable molecular tool for the selection of yeast members recovered from food or other environments.