Lager beers got their start in Bavaria, but it was a little South American spice that really kicked things off.
Scientists have known for decades that a hybrid species of yeast, Saccharomyces pastorianus, is the microbe that ferments lagers. It’s also well known that one parent of S. pastorianus is the common baking and brewing yeast Saccharomyces cerevisiae. But the other parent of lager yeast has eluded scientists, who have scoured Europe and North America looking for it.
Turns out they were looking in the wrong hemisphere. An international team of researchers led by Chris Todd Hittinger of the University of Wisconsin–Madison and Diego Libkind of the Argentinean National Council for Scientific and Technical Research in Bariloche has tracked the missing wild parent of lager yeast to the beech forests of Patagonia. The researchers report the capture of the newly discovered yeast, dubbed Saccharomyces eubayanus, online the week of August 22 in the Proceedings of the National Academy of Sciences.