Selection of Saccharomyces eubayanus strains from Patagonia (Argentina) with brewing potential and performance in the craft beer industry

Abstract

Saccharomyces eubayanus is a genetically diverse yeast isolated for the first time in Patagonia (Argentina), which has received special attention in research and brewing applications for being identified as one of the parents of the lager-brewing yeast. In the search for different and innovative products, the beer market has focused part of its efforts on innovation through the application of non-conventional and/or wild yeasts, as is the case of S. eubayanus. This study aimed to characterize the brewing potential of S. eubayanus and select the most promising strains in terms of beer production. Fifty S. eubayanus strains from different Patagonian locations were analyzed in small-scale fermentations. Based on its genetic characteristics and fermentative behavior a candidate from each of the five geographically structured subpopulations of S. eubayanus was selected for lab-scale fermentations. Fermentation performance, sugar consumption and production of aroma compounds were evaluated, and one strain was selected to assess for the first time the behavior of this wild yeast at a craft brewing scale. In these conditions, a decrease in fermentation capacity was observed, showing that S. eubayanus requires different handling compared to traditional brewing yeasts and set the basis for further fundamental and applied research at larger productive scales. This work supports and encourages the use of native non-conventional yeast in brewing for the production of innovative beers with greater product differentiation, giving rise to the possibility of granting a regional character to the products.