Differentiation of Saccharomyces cerevisiae strains isolated from fermenting musts according to their karyotype patterns

Pulsed field electrophoresis is a suitable technique for differentiation of Saccharomyces cerevisiae strains. In this work, karyotype analysis was used to study the ecology of the wild S. cerevisiae flora in musts in fermentation in the A.C. (Appellation Controlee) area of Valdepeٌas (Spain). In order to do this, 392 colonies isolated from different vats in different cellars, where dry yeast was never used to make wines, were submitted to the Countour Homogeneous Electric Field (CHEF) technique. Each of the resulting CHEF profiles was subjected to Cluster Analysis and four main karyotypes were found in this viticultural area.