What Do You Get When You Ferment With Kveik Yeast?

With the recent popularity of the more available Kveik yeast strains, many of your are wondering what the heck that is!  Wait, you mean there’s a beer yeast that I can ferment with upwards of 80° F and still get a clean and delicious beer? Yes, my friends, but let’s start with a quick history lesson!

Single Celled Vikings Fighting Sugar Molecules

Viking Yeast

The joke around here since we’ve had the opportunity to play with kveik (a word that simply translates as ‘yeast’) strains has been the mental image of a horde of tiny, single celled vikings, complete with swords, battle axes, and spiked helmets, and I fear that’s how I’ll always look at kveik strains, given their ancestry.

Simply put, for a very large part of history, kveik yeast strains were all that were available in Norway.  These strains were passed down generation to generation, family to family, preserved with very archaic methods so that everyone could make their home fermentations.  Many brewers would simply use a kveikstokker, which is just a dry log or ring of interlocking wood, to inoculate their homebrew. They would rehydrate this log in some of the first runnings during the lauter phase of their brew day, then add the entire thing to their beer!  When fermentation was complete, they would simply drain the fermentor and roll the log around in flour and hang it up to dry! No wonder these strains are so indestructible!

These yeast strains are fundamentally, and genetically, different than normal saccharomyces strains.  They have the ability to ferment extremely hot and fast without adding off flavors to the finished beer style, wash, cider or mead.  This means flavors like fusel alcohols, diacetyl and acetaldehyde like you would get from underpitching and fermenting way too hot.

While there are quite a few different kveik strains, which generally denote the region in Norway from whence they came, this week we’ll focus on the Voss kveik strains, since Loki from Imperial Organic Yeast is a Voss strain and we have a bit more experience with it.

Loki Fermentation Voss Kveik

Pitch It Light

One of the more fascinating aspects of these strains is that you can pitch them at super low pitching rates and still get an awesome, clean beer free from the yeast driven off flavors that you would get with a normal sacch strain.  These guys thrive at lower pitching rates, even though you can still pitch at normal rates and get a clean fermentation. Just like with any yeast, pitching light is going to get you more ester production, which isn’t necessarily a bad thing, since half the time that’s what you’re going for with a strain like this!  With higher temps, Loki is going to give you BIG orange, almost like the orange characteristics you get from Amarillo hops!

On Milk the Funks fabulous and expansive Wiki, they recommend a pitching rate of 1 to 2 million yeast cells per milliliter of wort, which is kind of insane if you think about it.  A normal ale yeast pitch accounts for 10 - 13 million yeast cells per milliliter, which really puts into perspective how not only versatile, but hearty this yeast is!  

Fire and Ice Fermentation Temperatures

Varying the Fermentation Temps

Kveik is working with an absolutely insane fermentation temperature range, and the profile changes just as much with the extremes.  While traditionally used to ferment farmhouse ales, this versatility opens it up to a wide variety of beers, from psuedo lagers to juicy IPA’s, and just about everything in between, just as long as it’s a nice dry beer style.  Our god of mischief produces a clean, lager-like beer at 65°, so is perfect for when you want to make a nice Helles or Mexican Style Lager for summer but don’t have the extra fermentation equipment.. 

As the heat rises, so does the fruit profile.  This means, again if you don’t have the extra fermentation equipment to control temperature, you’re not stuck with saisons for every brew day in the summer!  Why not branch out and make a dry and fruity Belgian Tripel or Belgian Blonde?  The coolest part is that it tops out around 100° F.  You didn’t mis-read that! 100 Degrees!

At higher temps, our favorite trickster god is also going to ferment FAST.  We’re talking a few days, while still maintaining a clean flavor profile, albeit super estery.  Talk about a quick turnaround for those beers you promised you’d make for a friend or an event, then ran out of time!  7 days? No problem! That doesn’t mean you should stray too far from your normal fermentation profile,, but in a pinch, it will work, and work well!

Kveikstokker Log for inoculation

Making Your Own Kveikstokker

Full disclosure:  we haven’t tried this yet, but thought it was a fun point to hit on given the extensive history of this strain.  It will probably take some trial and error, not to mention the teeth gritting fear that you just spent 8 hours making a beer, sanitizing your equipment, and keeping your process clean and sterile, to just drop a log into it and hope it’s not horribly infected!  That being said, it sounds like fun, and I like the thought of having a potentially weird house strain to pass down as a legacy, as well seeing the looks at group brew days when we just drop a seemingly random, seemingly dirty block of wood into the fermentor and close it up like it’s not super weird!

For the simplest method, get a nice piece of oak.  I like the idea of using a barrel stave, because that just makes sense!  You don’t need it to be huge, 6 to 8 inches long or so. Drill a hole about a half inch in the top so that you can attach a sterile string to hang it up, and drill a bunch of holes in it, say 1/4 to 3/8 inch.  The idea here is to maximize surface area for your yeast to attach to.

Next, boil the bejeezus out of it to sterilize it.  Use a nice, sanitized piece of twine to hang it up to dry after boiling.  This is all pretty counter-intuitive, but bear with me! This method has worked for literally hundreds of years!

Now for the fresh yeast!  After brew day, when you go to pitch your fresh Loki, pitch your fun new yeast log at the same time!  Let it stay in there during fermentation, string removed, and when you rack to your keg or bottling bucket, it will be left on the bottom.  Get your new piece of sanitized hanging string, and hang it up somewhere clean and let it dry! Use it to inoculate your next batch and see what happens!  I give you at least 80/50 odds of coming up with a clean beer! After we’ve played with this a little more, we’ll do a full write up!

There are many home brewers out there who already do this, and we’d love to hear you chime in with your process, because this is super fun!

There are cooler and more intricate ways to make wooden yeast rings, but you’ll have to shoot over to Poppyland Brewer’s Blog for better instructions, because they are WAY outside of my personal woodworking capabilities!

Imperial Organic Yeast A43 LOKI

Should I Use Loki In My Next Beer?

The answer, of course, is a resounding YES!  With summer heading our way, this is the perfect time to play with this versatile strain, whether you’re making a standard farmhouse ale, going for a clean lager-like profile, or want to go full Belgian fruity fun!  As homebrewers, we are always looking for cool new yeast to test out, and we always love versatile yeasts that widen the kinds of beers that everyone can brew, no matter how much or how little equipment they have on hand.  This is why we all homebrew!

For more really awesome info on kveik, different strains, and more origin info, check out Larsblog.  He has made a serious study of kveik yeasts, and has tons of great info!

Thank you all for reading!  We’d love to hear your experiences with Loki and different kveik strains in the comments below!  Don’t forget to check out our video with Imperial Yeast as we go behind the scenes and take a killer tour of their facility, as well as our other fun and informational videos at BrewChatter TV!  Don’t forget to connect with us on Facebook, Instagram and Twitter to stay on the up and up with everything fun and fermentational.  Brew On!
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