Researchers say the hybrid yeast that makes the world's favourite beer was probably created when a tree-dwelling Patagonian strain crossed the Atlantic with migrating birds
The Observer, Sunday 13 April 2014
Lager drinkers can thank the birds for their favourite tipple. That is the conclusion of US scientists who say the yeast involved in making their beloved amber nectar could have been spread round the planet by migrating birds.
The work, by researchers at the University of Wisconsin-Madison, follows up on the 2011 discovery that a key component of the yeast used to make cold-brewed beers came from Patagonia, in South America.
Lager – which, say its multitudinous fans, has a crisper, cleaner taste than warm-brewed ales – was first made by monks in Bavaria 500 years ago, using a yeast that has since been shown to be a hybrid of European yeast and another yeast. It was this latter yeast that was traced to colonies found in trees in Patagonia three years ago.
The discovery raised a critical question, however. How did that yeast make it from South America to Europe, a 7,000-mile journey, and there form a hybrid with an old world version? When the discovery of the Patagonian link was announced, most speculation focused on the idea that the yeast could have arrived in the timbers of boats of early traders to and from South America.