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''S.eubayanus'' is one of the probable parents of lager yeast (''S. pastorianus'') via the hybridisation with ''S. cerevisiae'' <ref name="libkind_2011"></ref><ref name="bing_2014"></ref>.
It was first isolated and described in 2011 growing within ''Nothofagus'' trees in Patagonia, Argentina. Since then, strains of this species have also been found in cold regions across the globe, including Tibet, China, the United States, Chile, and New Zealand. It has also been isolated from the wild in Ireland <ref>[https://academic.oup.com/femsyr/article/22/1/foac053/6874782 Sean A Bergin, Stephen Allen, Conor Hession, Eoin Ó Cinnéide, Adam Ryan, Kevin P Byrne, Tadhg Ó Cróinín, Kenneth H Wolfe, Geraldine Butler, Identification of European isolates of the lager yeast parent Saccharomyces eubayanus, FEMS Yeast Research, Volume 22, Issue 1, 2022, foac053, https://doi.org/10.1093/femsyr/foac053.]</ref>. ''S. eubayanus'' has been described as being cold-tolerant, and can grow between 4–25°C. It has been suggested that this trait was inherited by lager yeast.
Although only a small number of strains have been collected from the wild by scientists, ''S. eubayanus'' has a wide range of genetic diversity between different strains. Some strains show potential for brewing purposes, which is primarily characterized by how well they ferment maltose. [https://sfamjournals.onlinelibrary.wiley.com/doi/full/10.1111/1751-7915.13545 Mardones et al. (2020)] evaluated 10 strains of ''S. eubayanus'' and their potential for fermenting wort. Four of the strains were isolated from Chile, four from Patagonia, one from Argentina, and one from New Zealand. All of the strains efficiently fermented glucose and fructose, while none fermented maltotriose. Maltose utilization varied greatly across all of the strains with the Argentinian strain (CBS-12357) utilizing maltose the most and producing the most ethanol. Overall, there was no correlation to how well strains fermented maltose based on what country they were from. There was also a wide range of esters, higher alcohols, and carbonyl compounds produced by the different strains. For example, two of the strains of Patagonia (CL465.1 and CL450.1) produced some higher alcohols and acetate esters like 2-phenyethyl acetate (rose, honey) and 3-methylbutyl acetate (banana), while other strains (Argentinian strain CBS-12357 and Chilean strain CL216.1) produced more ethyl octanoate and ethyl decanoate (fruity and apple-like). Nearly half the strains produced very low levels of all of the compounds measured. Most strains produced insignificant levels of acetaldehyde, except for two of the Chilean strains <ref name="Mardones_2020">[https://sfamjournals.onlinelibrary.wiley.com/doi/full/10.1111/1751-7915.13545 Molecular profiling of beer wort fermentation diversity across natural Saccharomyces eubayanus isolates. Wladimir Mardones, Carlos A. Villarroel, Kristoffer Krogerus, Sebastian M. Tapia, Kamila Urbina, Christian I. Oporto, Samuel O’Donnell, Romain Minebois, Roberto Nespolo, Gilles Fischer, Amparo Querol, Brian Gibson, Francisco A. Cubillos. 2020. DOI: https://doi.org/10.1111/1751-7915.13545.]</ref>.