Rat Pack Brewing is back for part two of brewing with kveik. Part one focused on brewing with the Sigmund Gjernes Voss and Terje Raftevold Hornindal strains. This edition is going to focus on a few lesser-known, and less used strains.
Rat Pack Brewing: Kveik, Part Two
Bootleg Biology Oslo
The Oslo strain from Bootleg Biology is reported to ferment clean and lager-like. This strain, like most Kveik strains, can ferment hot and produce a clean beer. Unlike other strains, this is supposed to bring a neutral yeast profile, lending itself to pseudo-lager styles.
In my experience, this yeast has been deployed in a Kentucky Common, a style that relies heavily on malt character and a neutral yeast profile. While the beer was generally clean, there was a noticeable citrus character to it. It was fermented at a temperature of 80F/27C, so at the lower end of the temperature scale for a Kveik yeast.
As stated, it did produce a clean beer overall, but certainly not lager-like. The one thing that can be said is that with a long period of conditioning, both in a warm room and in cold storage, it did start to drop clear and the citrus character began to diminish quite significantly. There is more research/testing on my end to confirm that this was a replicable circumstance.
On the Bootleg Biology website, Oslo is stated as a quick fermenter (as quick as three days for a turnaround) and clean. This information is corroborated by Eik & Tid, a brewery in Oslo, Norway and the original source of the Kveik for Bootleg. If you want to dive further into their information as a brewery and in using this yeast, they supply more information on their Instagram and website.
Escarpment Labs Laerdal
The Laerdal Kveik strain might be one of the lesser-known commercially available Kveik strains currently, but it is not one to sleep on. This strain was released by Escarpment Labs out of Canada as part of “The Kveik Ring,” a series releasing strains that no one else seems to be, like Laerdal.
The commercial description reads, “This single strain isolate from the Laerdal Kveik (sourced from Dagfinn Wendelbo) ferments fast (like most kveik), flocculates well, and adds pineapple and orchard fruit aroma to beer. Ferments fast and is likely suited to Hazy IPAs and English ales.” This description is an apt one, as pineapple is a highly desirable character in New England-style IPAs.
Other brewing notes to be aware of are that this yeast is not known to have much or any biotransformative abilities when interacting with hops. Another important note that comes into conversation with Kveik often is pitching/fermentation temperature. When looking at the Kveik Registry and when emailing Richard Preiss of Escarpment Labs, the optimal temperature for this strain is 86F/30C.
Outside of the above notes, this is a hardy strain that has great shelf stability, as is the case with virtually all Kveik strains. The last brewing property to be aware of is the average attenuation of the strain, at which Preiss stated that in an average wort you could expect anywhere between 70-80% apparent attenuation.
This yeast is, much like most other Kveik strains, ideal for top cropping and can be dried for longer storage times.
While these two strains may not get the attention of the two in part one, they are not ones to turn away from. The Oslo strain may not ferment as cleanly as lager strains, but it can still make a fine beer in a much, much shorter period that with a longer lagering period can come off as extremely clean. And if you are looking for a fast and fruity fermentation, but find yourself wanting to change it up from Voss or Hornindal, then Laerdal is a perfect substitution to create delicious beers.