Lager-brewing yeast identified in Argentina Skip to main content

Lager-brewing yeast identified in Argentina


Galls The round galls on the Patagonian beech trees are full of yeast

Related Stories

Scientists have identified a yeast that led to the discovery of lager.
The researchers isolated the new species in the frozen forests of Patagonia in South America.
Their discovery suggests that this yeast crossed the Atlantic hundreds of years ago and combined with one traditionally used in Europe to make ale.
The discovery is described in the Proceedings of the National Academy of Sciences.
A lucky find The workhorse of brewing, the yeast Saccharomyces cerevisiae, is used worldwide to ferment fruit and grains to make wine, cider and ale.
Lager-brewing, which is fermented more slowly and at lower temperatures than ale, is presumed to be a later invention, and was likely stumbled upon when Bavarian monks moved their beer barrels into caves to store it.
In those caves, Saccharomyces cerevisiae, which prefers to grow just above room temperature, is presumed to have been outcompeted in the fermenting beer by a species that thrived at cooler climes.
The modern-day lager-brewing yeast, Saccharomyces pastorianus, which is a fully domesticated species, is probably a hybrid of this cool-loving strain and the ale-brewing species, and survives because brewers keep back a little of the lager each time to seed the next batch with the same yeast.
Lager's cradle "The hybrid almost definitely formed accidentally and people adopted it because the beer came out differently," said evolutionary biologist Chris Hittinger from the University of Wisconsin in Madison, US, who was one of the team behind the discovery.
A pint of lager (Credit: PA) The UK consumes 20 million barrels of lager each year
But researchers have long wondered where the original cool-loving yeast species came from.
That is until Dr Hittinger and his colleagues isolated it from a beech tree in the forests of Patagonia this year.
These forests, where daily lows average around -2C, are the perfect cradle for modern-day lager-brewing yeast. The species has been designated Saccharomyces eubayanus.
"I personally prefer lagers to ales, and I am very grateful that these two distant cousins met up in a Bavarian cellar hundreds of years ago," Dr Hittinger told BBC News.
Knowing the ancestral strain to the modern day lager-brewing yeast will help scientists pinpoint the effects of domestication in the genome of brewing yeasts.
And there is also the possibility that there are other undiscovered species of yeast in those Patagonia forests that could become the next best brew.

http://www.bbc.co.uk/news/science-environment-14592877

Comments

Popular posts from this blog

Chronology of the Press in Burma

1836 – 1846 * During this period the first English-language newspaper was launched under British-ruled Tenasserim, southern  Burma . The first ethnic Karen-language and Burmese-language newspapers also appear in this period.     March 3, 1836 —The first English-language newspaper,  The Maulmain Chronicle , appears in the city of Moulmein in British-ruled Tenasserim. The paper, first published by a British official named E.A. Blundell, continued up until the 1950s. September 1842 —Tavoy’s  Hsa-tu-gaw  (the  Morning Star ), a monthly publication in the Karen-language of  Sgaw ,  is established by the Baptist mission. It is the first ethnic language newspaper. Circulation reached about three hundred until its publication ceased in 1849. January 1843 —The Baptist mission publishes a monthly newspaper, the Christian  Dhamma  Thadinsa  (the  Religious Herald ), in Moulmein. Supposedly the first Burmese-language newspaper, it continued up until the first year of the second Angl

ARSA claims ambush on Myanmar security forces

Arakan Rohingya Salvation Army (ARSA) on Sunday claimed responsibility for an ambush on Myanmar security forces that left several wounded in northern Rakhine state, the first attack in weeks in a region gutted by violence. Rakhine was plunged into turmoil last August, when a series of ARSA raids prompted a military backlash so brutal the UN says it likely amounts to ethnic cleansing of the Muslim Rohingya minority. The army campaign sent some 650,000 Rohingya fleeing for Bangladesh, where refugees have given harrowing accounts of rape, murder and arson at the hands of security forces and vigilantes. Myanmar's military, which tightly controls information about Rakhine, denies any abuses and insists the crackdown was a proportionate response to crush the "terrorist" threat. ARSA have launched few attacks in recent months.  But the army reported that "about ten" Rohingya terrorists ambushed a car with hand-made mines and gunfire on Friday morning

Thai penis whitening trend raises eyebrows

Image copyright LELUXHOSPITAL Image caption Authorities warn the procedure could be quite painful A supposed trend of penis whitening has captivated Thailand in recent days and left it asking if the country's beauty industry is taking things too far. Skin whitening is nothing new in many Asian countries, where darker skin is often associated with outdoor labour, therefore, being poorer. But even so, when a clip of a clinic's latest intriguing procedure was posted online, it quickly went viral. Thailand's health ministry has since issued a warning over the procedure. The BBC Thai service spoke to one patient who had undergone the treatment, who told them: "I wanted to feel more confident in my swimming briefs". The 30-year-old said his first session of several was two months ago, and he had since seen a definite change in the shade. 'What for?' The original Facebook post from the clinic offering the treatment, which uses lasers to break do