From Lagering to Lager

June 26, 2024 8:28 AM

The Past, Present, and Future of Lager Yeast (Good Beer Hunting) No matter how much scientists and historians have searched—and they’ve literally hunted in forests, cellars, and old brewery buildings, and have run all the DNA testing that’s available to them—a void has existed at the heart of what is the world’s most popular and most consumed beer. But just within the last year, the latest detective work and scholarly research have led to a compelling new theory about lager’s true origins. After many centuries—spanning lager’s 14th-century beginnings to its present-day ubiquity—have we finally solved the foundational mystery behind the world’s best-loved beer?
posted by CrystalDave (10 comments total)

I love this kind of detail, it feels like it could be the launching point for a historical novel:

When what’s now known as the Reinheitsgebot—the Beer Purity Law—was signed by the Duke of Bavaria in 1516, it ruled that Bavarian beer could only be brewed with barley, and not wheat. Weissbier, which was mostly made with wheat, was therefore banned, and that made lagered beer—then known as braunbier—the sole beer of Bavaria.

The Bavarian royal family, the Wittelsbachs, had built themselves a braunbier brewery in Munich’s Alter Hof Palace in 1589, partly to save money from all the beer they were importing. That reveals a deeper concern: They were broke.

posted by spamandkimchi at 8:54 AM on June 26 [4 favorites]

Shouting
Lager lager lager lager
Shouting
Lager lager lager lager
posted by HearHere at 9:22 AM on June 26 [1 favorite]

The Reinheitsgebot always gets touted as the "World's First Consumer Protection Law". Makes sense, right? "Beer can only be made with malted barley, water and hops!" (They didn't incorporate yeast until a much later date.)

The reality is that it was aimed at preserving military readiness and raising taxes as anything else. Weissbier had gotten so popular that it was impacting wheat supplies and thus bread need for troops and the populace. The royals moved to shut that down, while preserving it for themselves.

As for Lager yeast, odds are really, really, really profoundly high that if have a "craft" lager - that it's made with a strain from the 34/70 family line. In tracking my club's happy hours - over a third (and now getting closer to half) of the beers sampled from California micros are lagers of some variety. The vast, vast majority of those are made with Saflager 34/70, White Labs 830 German Lager, Wyeast 2124 Bohemian Lager or Imperial Global - all the same strain more or less.

They're right that lager yeasts are less diverse than ale strains and in part that's because of the industrial nature of its production these days. If you want to make a fortune as the "Levis" of the brewing world, you figure out a way to make a clean, crisp lager faster and cheaper without sacrificing "quality".

There have been complicated schemes involving recirculating fermenting beer through yeast impregnated plates to speed up fermentation and remove the need to settle yeast from solution, using pressurized fermenters to reduce ester and sulfur production and thus reduce aging time, different fermentation schedules (Dr. Narziss mentioned in the article created a hybrid lagering scheme involving higher temperatures to reduce fermentation time, for instance. Man was an absolute giant in the modern brewing industry.)

And, unsurprisingly - attempts to find different yeast strains that can ferment warmer (less energy cost) and faster (time in tank is $$ lost). The Nova strain from Lallemand is an example of this - they tout the flavor differences in the article, but the primary sales pitch to brewers has centered on less strict temperature requirements and speed of fermentation. I'm just glad the hype around "clean kveik" strains has died down because while I find kveik to be interesting, I think trying to make "psuedo-lagers" with them is like using a butter knife to turn a screw - sure it will work but it's terrible at it, makes a busy and blood will probably be drawn.
posted by drewbage1847 at 9:39 AM on June 26 [8 favorites]

That's pretty neat. It's interesting that they seem to quickly dismiss the Tibetan origin of S. eubayanus - I have no doubt that Silk Road merchants' impulse to bring home weird foreign booze was any less than modern travelers', and they were at it for 1,500 years.
posted by McBearclaw at 10:15 AM on June 26 [1 favorite]

The yeast has been located in places as far-flung as Patagonia, Tibet, New Zealand, Wisconsin, and Dublin. The current theory is that wood or barrels made from Tibetan oak or walnut, which carried a culture of Saccharomyces eubayanus, ended up in a Bavarian brewery, but experts like Verstrepen question this. “Did some eubayanus really get lost on the Silk Road and make its way to Germany? I dunno. I believe there must have been a local population, but we cannot find it anymore.”

German popular and philosophical mysticism has had a pronounced Tibetan flavor for a long time, and it would be extremely and somewhat eerily appropriate if the lost mysterious ancestor of lager yeast turned out to be Tibetan after all.
posted by jamjam at 10:18 AM on June 26

I would suspect some of the quick poo-pooing of the Tibetan bit is from "well, that requires a big leap without evidence where there's potentially a simpler solution", but it is also way more plausible than where we were a few years back where some of Eubayanus's origins were tied back to Patagonia and that was really giving people fits because of what it would mean for generally understood trade/migration patterns at the time that lager yeast begins to rise.
posted by drewbage1847 at 10:18 AM on June 26 [2 favorites]

If we overlap science and history once again, we find two possible reasons for that missing piece. From 1300 to 1700, Europe went through several small ice ages, and those colder periods may have created a temporary environment in which the cold-loving Saccharomyces eubayanus could live.

These same little ice ages have been associated with witch trials and other wide spread popular delusions because they also foster the development of ergot in grain crops, and ergot produces hallucinations among other untoward effects:

Most commonly attacking rye, ergot infects and replaces the cereal grain with a dark fungal body called a “sclerotium.” When made into bread or otherwise ingested (e.g. barley beer), it causes ergotism, also known as “St. Anthony’s Fire” or “Devil’s curse.” Convulsions, muscle spasms, vomiting, hallucinations, and a gangrenous pain where the victim’s limbs, fingers, toes, and nose were “eaten up by the holy fire that blackened like charcoal” characterize ergot poisoning. Victims often lost parts of their extremities or entire limbs due to blood vessel constriction associated with gangrenous ergotism.

A yeast which could thrive in the cold such as Saccharomyces eubayanus would presumably need to be able to compete with ergot in its natural habitat, and may have been important during those ergot encouraging little ice ages in preventing batches of brewed beer from 'going off' and becoming completely undrinkable due to uncontrolled ergot multiplication, but would therefore and nevertheless be more likely to produce an hallucinogenic but drinkable beer in the presence of ergot infestation.
posted by jamjam at 11:10 AM on June 26 [1 favorite]

Neither ergot fungus nor wild yeast on the grain will make it into the wort, having been killed in the malting process or the boil. The ergot produces alkaloids which are not entirely degraded by the brewing process, so can have an effect on the drinker, but there would be no live ergot fungus in the wort or beer. In other words, the barley is infected with ergot, not the beer itself, so there is no interaction between the brewing yeast and the ergot fungus.
posted by ssg at 11:57 AM on June 26 [1 favorite]

It is very, very unlikely that 14th, and 15th century yeast mixtures themselves were not contaminated with viable ergot.

The more so the more it common it was in the environment as it certainly would have been in colder years.

The Wikipedia article on ergot describes it as "impervious to heat and water", which is certainly overstating the case, but spores commonly do survive boiling though I was unable to find a reference which specified whether ergot spores do or do not.
posted by jamjam at 12:50 PM on June 26

Ergot has a complicated life cycle, with two kinds of spores as well as the sclerotia that are what gets ground up in flour and contaminates bread. Neither spore is a yeast-type spore, so neither could multiply during the fermentation process, assuming they survived the heat treatment (the sclerotium is the stage that is pretty impervious, not the spores). I don't know if yeast cultures could become infected with ergot mycelium; if they did, I imagine a brewer would see it and throw it out.

We used to study sorghum ergot in our lab, but we did not try to make sorghum beer.
posted by acrasis at 5:56 PM on June 26 [2 favorites]