How the world’s most popular beer was created by accident

By Mark Waghorn via SWNS

The world's most popular beer, lager, originated by accident In Bavaria more than 400 years ago, according to new research.

The yeast used to brew cold beer arose in Munich at the court of Maximilian the Great, after two different yeasts came into contact - and mated.

Their coupling created the species Saccharomyces Pastorianus - which works at a much slower rate at cooler temperatures in caves and cellars.

Historically, all beers were fermented with one particular strain named Saccharomyces Cerevisiae - used for thousands of years.

It ferments warm and relatively quickly - producing what we refer to as ale.

Lead author Dr. Mathias Hutzler, a beverage microbiologist at the Technical University of Munich, said: "Saccharomyces pastorianus is responsible for the production of bottom-fermented lager beer.

"It is a hybrid that arose from the mating of the top-fermenting ale yeast Saccharomyces cerevisiae and the cold-tolerant Saccharomyces eubayanus around the start of the 17th century."

Photo by YesMore Content on Unsplash

His team combined documents with evolutionary and genetic data to trace the beverage's origins to the Munich brewery of the Duke of Bavaria in 1602.

They found S. cerevisiae contaminated a batch of beer brewed with wild variant S. eubayanus at a wheat brewery in the small town of Schwarzach in southern Germany.

Brewing is one of the oldest human industries with evidence of fermented beverages from China from at least 7,000 years ago, and from Israel from up to 13,000 years ago.

Modern brewing developed in Europe, where, until the Middle Ages, most beer brewing was associated with Saccharomyces cerevisiae.

This is the same species of yeast that is still used today to make ale-style beer, wine, and bread.

Most beer made nowadays, however, is a lager beer, not ale, and there is considerable interest in understanding the historical shift from ale to lager in Europe.

Lager brewing uses a different species of yeast, Saccharomyces pastorianus. The identity of its second parent was a mystery until 2011, when Saccharomyces eubayanus was discovered in the Patagonian Andes in Argentina.

The study shows S. pastorianus developed in three stages. First, the yeast strain S. cerevisiae came to Munich from Bohemia, where brewers had made wheat beer since at least the 14th century.

S. cerevisiae that was introduced into the Munich brewery in 1602 mated with S, eubayanus, which was already involved in making beer - to give rise to S. pastorianus.

The new species of yeast was distributed around Munich breweries first, and then throughout Europe and the world.

Lager now accounts for approximately 90 percent of the beer consumed annually. No one had figured out how S. pastorianus came about - until now.

Beer was always a valuable commodity and its production was regulated carefully. In Bavaria, a brewing law from 1516 permitted only fermentation of 'lager-style' beer.

But in neighboring Bohemia, an excellent wheat beer made with S. cerevisiae was produced and vast quantities were imported.

To limit the economic damage, in 1548 the Bavarian ruler, Wilhelm IV gave Baron Hans VI von Degenberg a special privilege to brew and sell wheat beer in the border regions to Bohemia.

When the grandson of Hans von Degenberg failed to produce an heir, the family finally died out and, in 1602, the new Bavarian ruler, Maximilian the Great, seized the special wheat beer privilege himself and took over the over the von Degenbergs' Schwarzach breweries.

In October of that year, the yeast from the wheat brewery was brought to the Duke's court brewery in Munich - and S. pastorianus was born.

Lead author Dr. Mathias Hutzler, of the Technical University of Munich, said: "There is a certain irony that the inability of Hans VIII von Degenberg to produce a son triggered the events that led to the creation of lager yeast.

"As one lineage died out, another began. No heir - but what a legacy he left for the world!" The study is in FEMS Yeast Research.

Maximilian I, occasionally called the Great, was a member of the House of Wittelsbach. He ruled as Duke of Bavaria from 1597.

His reign was marked by the Thirty Years' War during which he obtained the title of a Prince-elector of the Holy Roman Empire at the 1623 Diet of Regensburg. he died in 1651, aged 78.