Physiological characterization of Saccharomyces uvarum and Saccharomyces eubayanus from Patagonia and their potential for cidermaking

Abstract A diversity of yeast strains belonging to the cryotolerant fermentative species S . uvarum and S . eubayanus have been recovered from natural habitats and traditional fermentations in North Patagonia. The aim of this work was to evaluate the most relevant physiological features in a set of Patagonian strains belonging to S . uvarum and S . eubayanus , in order to analyze their potentiality to be used as starter cultures for cidermaking elaborated at low temperature. We evidenced that S . uvarum strains isolated from natural habitats ( Araucaria araucana bark) showed similar physiological features to S . eubayanus strains obtained from the same habitat, and different from S . uvarum strains from fermentative environments (apple chichas ). We also confirm the capacity of S . uvarum to produce high glycerol levels, low acetic acid and elevated production of the higher alcohol 2-phenylethanol and 2-phenylethyl acetate and demonstrated similar properties in S . eubayanus . Finally, we evidenced for the first time the antagonistic activity of S . eubayanus and selected three strains (two S . uvarum and one S . eubayanus ) bearing the best combination of features to be used as a starter culture in cidermaking.