IT’S A question that could tax the finest pub quiz brains: what country can claim to be the origin of lager? It seems now that scientists have come up with the answer: Argentina.
Lager brewing may have begun in Germany 500 years ago, but it would never have come into existence were it not for the arrival of an immigrant yeast from South America.
After years of searching, scientists have discovered the origins of the yeast that made lager possible. It came from the beech forests of Patagonia, where it lives even today in the sugary beech galls caused by insect infestation.
“People have been hunting for this thing for decades,” said Prof Chris Todd Hittinger, a US-based scientist involved in the discovery along with colleagues in Portugal and Argentina.
They publish details of their findings this morning in the US journal, Proceedings of the National Academy of Sciences.
Lager production arose only 500 years ago in the caves and monastery cellars where for centuries the monks brewed ales and fermented wine and bread.
Brewing changed, however, when a new kind of yeast appeared, one that could produce golden lager. Not only that, it could deliver this brew when cold-fermented.
Bavarians were the first to produce the resultant lager beer, but could not have imagined it would burgeon into the €180 billion a year worldwide industry it is today.
Scientists used DNA analysis to discover that the yeast that delivered lager was actually a mutant, a merger of two yeast forms. They also showed the yeasts were as different in an evolutionary sense as humans are from chickens, the researchers said.
Geneticists searched through the 1,000-odd known species of European yeast but found no match for the lager-producing mutant. They then expanded their search to other parts of the world, eventually finding a match amongst the yeast genomes held by the Institute for Biodiversity and Environmental Research in Bariloche, Argentina.
The scientists speculated that the yeast made the astounding 7,000-mile journey from the southern tip of Argentina to the brewing cellars of Bavaria either hitchhiking on beech timbers shipped to Europe or secreted in the stomach of a gall mite that got delivered with the timber.
The Argentine yeast was a definitive genetic match. “It is clearly the missing species. The only thing we can’t say is if it also exists elsewhere [in the wild] and hasn’t been found,” said Prof Hittinger.