Wow, summer is flying by – its already time for the 5 month follow-up on my drying kveik experiment! For those of you new to this experiment, several months ago I dried some Voss Kveik, and have been providing monthly updates on its viability since. For those wanting the back-story:
- The initial drying
- Viability at 1 month
- Viability at 2 months
- Viability at 3 months
- Viability at 4 months
- An unexpected update from an even older sample
Drying Kveik – Viability at 5 Months
Viability continues to decrease in lock-step with past months, with the kveik loosing 6-8% of viability per month. Viability currently stands at 59%. At this rate we should reach 50% viability somewhere between 6 and 7 months post-drying. I would estimate that would be enough to pitch this yeast directly, without a starter. For longer storage, a starter is likely needed.
As per my estimate last month, this data is consistent with a maximum usable lifetime (e.g. ~1% viability) of ~40 months. That is over 3 years.
As I described last month, the viability is not likely a perfect estimate as dividing cells also accumulate the dye. As such, viability is likely slightly higher than I have measured here.
This is the penultimate entry in this experimental series. Look for next months post for the final viability count, plus a deeper dive into using drying as a way to store kveik. So join me in late August or Early September for the conclusion to this experimental series.
Prior to then I’ll also have a recipe and tasting note for an IPA brewed with this batch of dried kveik – look for that sometime in the next two weeks.