Saccharomyces in Traditional and Industrial Fermentations from Patagonia

Abstract

A large variety of fermented foods and beverages with traditional and cultural value have been described in the world, including industrial products such as wine, cider, and beer as well as traditional ones. In contrast with the massive scientific information available about the microbiota responsible for winemaking, yeasts responsible for most traditional fermented beverages around the world remain undiscovered. Both industrial and traditional fermentation processes coexist in Patagonia, making this region an ideal scenario for fermentative yeast diversity studies. The most relevant feature of this area is the fact that most traditional processes are produced at low temperature (below 20 °C), which directly affects the microbial diversity. We identified and characterized fermentative yeasts present during industrial fermentations of wine and cider and traditional fermentations (chichas) obtained from wild apples and Araucaria araucana seeds, substrates typically used by aboriginal communities to prepare soft alcoholic beverages. As a general rule, only Saccharomyces cerevisiae strains were obtained from wines and ciders, and they showed a close genetic relationship with European strains of this species. In traditional fermentations, commercial bakery and European wine strains of S. cerevisiae were detected as pure or mixed cultures with Saccharomyces uvarum, a cryotolerant species. This last species was also isolated from A. araucana seeds in Patagonian forests together with Saccharomyces eubayanus, another cryotolerant species of the genus. Genetic information obtained from the analysis of S. uvarum from apple chichas evidenced a closer relationship to industrial (European) strains than to natural (Patagonian) strains of this species. North Patagonia is an interesting scenario to study cryotolerant (S. uvarum and S. eubayanus) yeast diversity studies, and a source of new strains with potential biotechnological interest.