The cerveza report
Lager and the Argentinean connection
Lager (derived from the German word “lagern,” which means “to store” or “to rest”) is produced with a hybrid yeast: a fusion of domesticated yeast used to ferment wine and leavened bread, and another, until recently unidentified, distantly related species. Molecular geneticists from round the world, led by José Paulo Sampaio and Paula Gonçalvez of the New University of Lisbon, had been trying to identify the “mystery yeast.”
In 2011, Diego Libkind, a collaborator with the Instituto de Investigaciones en Biodiversidad y Medioambiente in Bariloche, Argentina, found the elusive yeast (which makes it possible for lager to be brewed at cold temperatures) in galls infecting beech trees in Patagonian forests. According to Libkind, “[t]hey fall all together to the [forest] floor where they often form a thick carpet that has an intense ethanol odor.”
The yeast, named Saccharomyces eubayanus, was studied at the University of Colorado School of Medicine where Chris Todd Hittinger, Jim Dover and Mark Johnsston sequenced its genome.
The group of scientists speculate that the Argentinean yeast made it across the Atlantic in the 1400s as European maritime merchants went back and forth; perhaps the microscopic yeast attached to a piece of wood, or traveled in the stomach of a fruit fly – quién sabe?
So, there you have it, another story to share when imbibing lager, one of the most popular drinks in the world.
You can read more about this fortuitous encounter in the Proceedings of the National Academy of Sciences (pnas.org/content).