If you love lager beer, you should thank Christopher Columbus for it. The never-ending mystery of where the yeast that keeps the cold-temperature for lager beer fermentation has been solved, in the lush forests of Patagonia in Argentina.
Human beings have been making beer since the ancient times. The very first evidence is the barley beer in Sumeria approximately 6,000 years ago, which likely is a fermented, thin, drinkable gruel. In Europe, similar kinds of yeast used to make bread and wine were utilized to create ale-type beers, a process that was well refined in the Middle Ages.
Came 15th century, something historical happened in Bavaria. Beers kept in the cold, damp caves and cellars, usually by monks, started to ferment. A brand new kind of slow-growing, cold-tolerant yeast had made its way into the area, making bottom-fermenting beer type possible for the first time.
Lager has since become so prominent that it is now the most popular approach for making alcoholic drinks, with more than 250 billion US Dollars in worldwide sales in 2008.
This was made possible because of the yeast called Saccharomyces pastorianus, a fusion of a popular ale-yeast named Saccharomyces cerevisiae and other, unknown, cold-tolerant yeast.
At first, many scientists could not find the other half of the yeast fusion in the wild. They searched for more than 1,000 yeast species known yet didn’t find a match.
However, a group of researchers from different countries have found the home ground of this magical yeast that has made a lot of sporting events so much more satisfying.
It comes from the alpine region at the tip of South America, in the beech forests of Patagonia. The yeast resides in galls that infect the trees there and is a 99.5% match for the 'missing link' half of the lager yeast.
The newfound yeast was named Saccharomyces eubayanus.
Chris Todd Hittinger, a University of Wisconsin-Madison genetics professor and a co-author of the study, said: "Beech galls are very rich in simple sugars. It's a sugar rich habitat that yeast seem to love."
As a matter of fact, the yeast is so active in the galls that they instinctively ferment. "When over mature, they fall all together to the (forest) floor where they often form a thick carpet that has an intense ethanol odor, most probably due to the hard work of our new Saccharomyces eubayanus," Diego Libkind of the Institute for Biodiversity and Environment Research in Bariloche, Argentina, said.
This New World yeast entered Europe just as the Columbian exchange between Europe and the Americas was commencing. It is likely that beech wood from Argentina was utilized to produce something that ended up in a monastery. And then it happened; it found its way to where beer was brewed. And the rest, beer lovers have grounds to be thankful for, was history.