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Kveik
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[[File:Kveikstokk.JPG|thumb|300px|right|Kveikstokk with yeast slurry on it. Images provided by [https://www.facebook.com/groups/MilkTheFunk/permalink/2237938229567712/ Antonio Golia ("Homebrew Condor").]]]
As Norwegian farmhouse brewers only brew 2-3 times per year, kveik has adapted to being dried and stored for long periods of time in-between usage, which is unique among most domesticated yeast <ref name="garshol_preiss_mbaa" />. Storing the kveik in a dried form allows the yeast to survive longer than if it is kept as a wet slurry, and might help prevent contaminants from surviving. Wooden carvings are used to store dried kveik. Their use is simple: drag the kveik ring (more broadly known as a "twisted torus" <ref>[https://www.academia.edu/38819003/Scandinavian_Yeast_Rings_-_the_curious_case_of_the_Twisted_Torus "Scandinavian Yeast Rings - the curious case of the Twisted Torus". Susan Verberg. 2019.]</ref>, or more specifically called a "gjærkrans" or "yeast wreath" in Norwegian when used for yeast <ref>[https://twitter.com/larsga/status/1118151239173328896 Lars Marius Garshol. Twitter feed. 04/16/2019.]</ref>) or kveikstokk through the krausen of a fermenting beer, and then hang the ring/kveikstokk to dry. On the next batch, the ring/kveikstokk is dunked into wort to reactivate the yeast <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1505143962847146/?comment_id=1505145579513651&reply_comment_id=1505163232845219&comment_tracking=%7B%22tn%22%3A%22R%22%7D Lars Marius garshol. Milk The Funk Facebook group post about using a kveik ring. 2017.]</ref>. Note that not all yeast reacts well to drying. Kveik has this exceptional ability. For example, ''Brettanomyces'' is known to not be tolerant of drying/desiccation <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/2237938229567712/?comment_id=2237959286232273&comment_tracking=%7B%22tn%22%3A%22R%22%7D Justin Amaral. Milk The Funk Facebook group post on kveikstokk and drying ''Brettanomyces''. 08/16/2018.]</ref>.
Dried kveik should be stored in the freezer, and has been known to last at least 20 years in this way. [http://suigenerisbrewing.com/index.php/2019/05/24/drying-kveik-part-4-3-months/ Microbiolgist Dr. Bryan Heit measured viability of kveik] that was dried using a dehydrator and stored in a home freezer, and found that viability decreased by about 6-8% per month. Dr. Heit estimated that at 6 months, the kveik would be at about 50% viability, which is good enough to pitch directly into wort without a starter. Therefore, if the kveik has been frozen for 6 months or less, dried kveik can be thawed and simply added to a liter or so of ~30°C (86°F) wort for 2-4 hours before adding that to the main batch of wort. If the dried kveik is older than 6 months, a starter is recommended <ref name="garshol_preiss_mbaa" /><ref>[http://suigenerisbrewing.com/index.php/2019/04/25/drying-kveik-2-months/ Dr. Bryan Heit. Sui Generis Blog post about dried kveik viability over time. 04/25/2019.]</ref>.