Scientist have bred new yeast strains to brew new beers?
I’ll drink to that!
Hey all you adults of legal drinking age, Julian here for DNews.
I’m fond of beer, particularly lagers.
But they’re all kind of samey, like the difference between vanilla and french vanilla.
Ales, on the other hand, come in every color of a gold to brown rainbow and they have a
big variety of flavors.
Why is that?
Well to find out, first you need to know a little history.
Ale has been around for about 7,000 years and probably started as a happy accident.
Leave some barley and water out in the sun, some airborne fungus gets in there and goes
to town on the barley’s sugars, converting it to energy through a process called fermentation,
and the waste product is alcohol.
I wonder who the first guy was that was willing to drink nasty fermented warm barley water.
Probably the same guy who got the first hangover.
Lagers though are much newer to the scene.
They only started popping up in europe in the 1500s, right around the time Europeans
started making trips to the new world.
It’s not a coincidence: the fungus used for fermenting lager is a hybrid of the yeast
used for ales, Saccharomyces cerevisiae, and another yeast indigenous to Argentina, Saccharomyces
eubayanus.
It wasn’t intentional, but somehow the S. eubayanus must have hitched a ride back to
europe and mixed with the local fungus.
The new yeast species, called Saccharomyces pastorianus, needs colder temperatures to
ferment sugar and at the end of fermentation it sinks to the bottom of the mix instead
of rising to the top.
Oh and it’s got 4 sets of chromosomes, making it allotetraploid.
Not necessary to know, but still pretty cool.
Getting those parent species to rumble in the fungal jungle and still make baby yeast
that are good for brewing isn’t easy though, and it needs human help to keep propagating.
The result is we’ve been making the same strains of S. pastorianus over and over and
using them for our lagers, and that’s why most of them taste pretty much the same.
So knowing this, what if we bred new yeast for new lagers?
Researchers at the University of Leuven in Belgium did just that.
They did the microbial equivalent of putting S. eubayanus and S. cerevisiae in a room,
lighting some candles, putting on some Marvin Gaye, and letting nature do its thang.
And do its thang they did.
To quote the researcher Dr. Kevin Verstrepen, "We were able to get some serious sexual action
between our yeasts, which resulted in hundreds of new lager yeast strains."
Serious sexual action.
Those are a PhD’s words, not mine.
They tested 31 of the strains on a small scale, and while some of them were terrible, 10 of
them performed well in terms of flavor and fermentation speed.
Verstrepen claims, “Two were magnificent.
They fermented more quickly than the commercially used reference lager yeast that we compared
them to, and they produced really nice flavors.”
I’d like to see this taken to the next logical step.
Instead of breeding the yeast and hoping for the best combination of genes, skip the middle
man altogether and genetically modify the yeast.
Select your favorite flavor and aroma elements and splice them right in, why not?
I’m picturing a future a hundred years from now where hobbyists can custom make yeast
in their garage.
Craft microbrewing?
Try craft microorganism brewing.
I know as soon as you bring up genetically modified food, some people freak right the
geek out.
Laci Green talks about the deal with GMOs here.
Would you drink a beer that had been made with genetically modified yeast?
I mean, there’s no actual yeast in it and we’re just combining genes from yeast species
we’re already breeding together.
I’d take a swig!…
But I’d do that for most beers.
Anyway let me know in the comments, subscribe for more, and I’ll see you next time on
DNews.