What is the Kveik Strain?

A particular strain seems to be catching some traction in the homebrewing and commercial brewing world as of late. The Kveik Strain. So the question you all came to see answered: what is it?

I was browsing the Milk the Funk Wiki (check them out if you haven't already, their facebook too!) doing some research on the mixed fermentation styles when Kveik caught my eye. I've had a few customer asking about it, I've been curious myself. I briefly saw it in the shops when Imperial Yeast brought their Loki seasonal strain through; it has since become a year-round strain. One particular thing about it caught my eye immediately: the fermentation temperature range. The Imperial strain fermented anywhere from 65 to 100F! 

That wasn't something I'd seen before. The strain went out of sight, out of mind a bit for me until tonight, when I poked my head out of WildBrews to look at the MtF wiki. After a recent talk with Erik & Nik about selecting a few specialty strains to bring to the shop, this looked a like a solid candidate. So I read on.

The word 'Kveik' is specifically a dialect word for 'yeast' in Norwegian. It is specifically a non-pure yeast strain that was used traditionally in Norwegian farmhouse ales. It can also rarely be seen alongside lactobacillus, making it a mixed fermentation strain in such case. The strain was commonly found in Norwegian brewing, and was passed down generationally and among neighbors and friends. As a result, many variations of the Kveik strain exist, and several yeast labs sell varying strains. 

One of the most unique things about this strain is its ability to ferment other beer styles outside the farmhouse category, including the New England IPA, several English styles, as well as cider, mead, and even distiller's washes.

Kveik is a non-phenolic, ester-strong, resilient yeast with several varying characteristics depending on the specific strain. A unique characteristic of Kveik is its ability to ferment at higher temperatures without off-flavor production (fusel alcohols, diacetyl, acetaldehydate). The Kveik yeast has seen successful fermentations anywhere from 40 to 109F, although usually used between 80 to 100F. Broadly speaking, the yeast tends to produce stronger esters when fermented at higher temperatures, and subdued esters below 68F. Fermentations below 68F are often described as clean, and slightly fruity. Kveik tends to be very alcohol tolerant, up to ranges of 13% to 16%. It is noted as being a very flocculent strain as well.

Another unique aspect of the Kveik yeast is that, similar to some Belgian strains, you can tweak the pitch count for a desired effect. A low to very low pitch rate leans the yeast towards heavier ester production, while a more standard ale pitch rate will subdue the ester production. Do note that due to the many differing strains of Kveik, you may want to use some experimentation to find the pitch rate and fermentation temperature you enjoy the most. Fun fact, the Milk the Funk wiki notes that traditionally, Norwegian brewers would perform a yeast scream when pitching the yeast, as to ward off supernatural spirits that might turn the beer sour. I'm not opposed to trying it.

Below is a data display of sensory notes I grabbed from the MtF wiki that Richard Priess performed to determine the difference between many of the Kveik strains:

"Kveik cultures have a wide range of fruity aromas, which is a result of above-threshold production of fatty acid esters, such as ethyl decanoate and ethyl caprylate. Richard Preiss from Escarpment Laboratories shared his sensory notes after doing trial fermentations with various kveik strains/cultures. Fermentations were at 30°C in standard wort (1.050, 20IBU) with single strains, not the mixed cultures. 2/3 tasters were blind to the beers and order prior to tasting. This is a single data point on sensory information:

• Sykkylven 1 - clean, fruity, malty, rum-like. big, round, malty, slightly hot
• Sykkylven 2 - subtle fruit, malt accented, slightly lagery-sulfury, lightly floral. medium body
• Laerdal 2 (Laerdal 1 - data not available) - Lightly fruity, slight rubber, floral, sweet taste
• Stranda 1 - citrus, red apple, very clean and dry, balanced
• Stordal (framgarden) 1 - big citrus ester, slightly hot, red apple, floral, malty
• Stordal (framgarden) 2 - red apple, slight crisp/sulfury (pleasant) lagery character, floral, slight tropical fruit, slight tartness
• Stordal (ebbegarden) 1 - rum-like, slightly hot, medium mixed esters, round and malty
• Stordal (ebbegarden) 2 - Christmasy, citrus, red apple, floral, clean and balanced flavour
• Muri 1 - Earthy, herbal, sulfury, apple, pear, very slight clove, not super dry despite ridiculous attenuation (~95%)
• Voss (Gjernes) 1 - Orange, floral, balanced flavour, good body
• Voss (Gjernes) 2 - Cidery, floral, slight earthiness, slight orange, clean, dry
• Hornidal 1 - Tropical, pineapple, rum-like, caramel, citrus, balanced malt/hop
• Hornidal 2 - Floral, rose-like, sulfury, orange, rum-like, very malt accented
• Hornidal 3 - Orange, red apple, rum-like, caramel, balanced
• Granvin 1 - Lower intensity orange, red apple, slight pineapple, textbook “Kveiky”, balanced
• Granvin 2 - Balanced esters, not as intense - citrus, slight (pleasant) sulfur, dry and thin
• Granvin 3 - very muted aroma, clean flavour
• Granvin 4 - floral (rose), honey, slight diacetyl, medium-low esters, complex but not necessarily good
• Granvin 5 - light fruit, light floral, rubber, sweet taste.
• Granvin 6 - fruity, floral, rum-like, citrus, slight diacetyl, balanced flavour
• Granvin 7 - Slight fruity, very thin and astringent
• WLP001 (control) - very fusely/hot, subtle floral note.

Note regarding Granvin strains: Preiss is still trying to sort out which Granvin yeasts are duplicates and which are unique."
I figured this data may be useful to those looking to select a particular strain.

If you're interested in reading more about this particular yeast, visit the Milk the Funk wiki here. I got most of my information on this yeast from them, thanks to them for making this article possible. While you're there, maybe read up on some of the other cool yeast and bacterias they've wrote some amazing wiki articles on. Also check out their Facebook page! I'm not receiving compensation for promoting them, I promise.

We'll be bringing some of these cool specialty strains to the store soon for preorders, so keep an eye on your Facebook, Instagram, or on our store homepage for them when they touch down!

Got any questions? Corrections? Personal Experiences? Let us know in the comment section below, or on our Facebook or Instagram page.

See everyone soon, -Owen Bankson

References:
Milk the Funk Wiki: Kveik
http://www.milkthefunk.com/wiki/Kveik

Sensory Testing, Richard Preiss, Escarpment Laboratories
https://www.escarpmentlabs.com/

Imperial Organic Yeast: Loki Strain
https://www.imperialyeast.com/organic-yeast-strains/