Academics in Ireland and Germany have traced the origins of lager beer to a brewery in Munich at the start of the 17th century, a new study has found.
The exact history of how the yeast used to make the traditional lager beer came into being has to date been speculation, however new research proposes one answer.
Prof John Morrissey, of University College Cork’s (UCC) school of microbiology, said it appeared the lager yeast originated by chance when wheat beer and brown beer were being made in the same brewery for several years.
At the time wheat beer was common in the German province of Bohemia and imported into Bavaria, which at the time had strict rules on how beer could be brewed.
In the mid-1500s a German nobleman was granted a dispensation allowing him to brew wheat beer in Bavaria. However, years later when his grandson died without an heir, the family’s property was seized by the Duke of Bavaria.
This resulted in the production of their wheat beer being moved to the Munich Hofbräuhaus in the early 1600s, where traditional Bavarian brown beer was already being brewed.
The new research from UCC and Technical University of Munich said the two types of beer were brewed “side by side” for several years.
Prof Morrissey said it was likely the two types of yeast mixed as a result of the brewery using the same wooden barrels and equipment. “Bohemian yeast mated with a Bavarian yeast,” he said.
The result was a new strain of yeast that is responsible for the common lager beer seen today, he said.
The research, published on Thursday in the FEMS Yeast Research journal, said this early 1600s period in the Munich Hofbräuhaus was the “most likely scenario” for the unintended creation of lager yeast.
Prof Morrissey said over the years the yeast was shared by Munich brewers, seeding it as one of the most popular beers in the world. “Brewers came to Munich to learn about their methods. It’s because of them sharing the yeast that it went all over,” he said.
The chain of events was down to several instances of “chance”, which resulted in a new species of yeast “that changed the world of beer”, he said.
