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Kveik

415 bytes added, 13:18, 3 January 2019
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[[File:Kveik microscope.jpg|thumbnail|right|The dried kveik samples (Stordal) showed much better viability/cell health (less granulated/wrinkly appearance) than the liquid samples (eg Hornidal). However, some of the liquid samples were pretty healthy too (Voss). Source [https://www.facebook.com/photo.php?fbid=10205280742451727&set=gm.1336954522999425&type=3&permPage=1&ifg=1 Richard Preiss of Escarpment Labs].]]
Thanks to efforts by Lars Marius Garshol and Håken Hveem, and Norwegian farmhouse brewers Svein Rivenes, Sigmund Gjernes, Bjarne Muri, Terje Raftevold, and others, kveik has been made commercially available to brewers around the world. Much of the analysis has been performed by the [http://www.ncyc.co.uk National Collection of Yeast Cultures (NCYC)] and [[Escarpment Laboratories]]. See also the [http://www.garshol.priv.no/download/farmhouse/kveik.html Kveik Registry] being maintained by Lars Marius Garshol.
Analysis has also been performed at the Norwegian University of Science and Technology (NTNU) by [https://brage.bibsys.no/xmlui/handle/11250/2390204 Truls C Rasmussen], as well as [[Escarpment Laboratories]].
* [https://www.facebook.com/groups/MilkTheFunk/permalink/2277955402232661/ Updates to the Escarpment Laboratories (Preiss et al.) analysis on MTF.] and their published paper [https://www.frontiersin.org/articles/10.3389/fmicb.2018.02137/full "Traditional Norwegian Kveik Are a Genetically Distinct Group of Domesticated ''Saccharomyces cerevisiae'' Brewing Yeasts"].
In general, most of the cultures of kveik that have been analyzed contain more than one strain of ''S. cerevisiae''. The exact number of strains that is present in a given kveik culture is difficult to analyze; generally labs with better equipment and more time can identify more strains than others. Some kveik cultures contain multiple strains of closely related strains of ''S. cerevisiae'', which while others contain a more diverse group of strains <ref name="garshol_preiss_mbaa" />. ''S. cerevisiae'' was the only species in all of the kveik cultures analyzed by Preiss et al. (2018) , except for the Muri kveik. The Muri kveik contains a single isolate of what appears to be a domestic (human produced) hybrid between ''S. cerevisiae'', ''S. eubayanus'', and ''S. uvarum''. Of the 9 kveik cultures analyzed by Preiss et al. (2018), only Muri, Simonaitis, and Stranda contained only one strain of ''S. cerevisiae'', while all of the others contained more than one strain of ''S. cerevisiae'' up to 9 strains in the case of Granvin (see [https://www.frontiersin.org/files/Articles/409253/fmicb-09-02137-HTML-r1/image_m/fmicb-09-02137-t001.jpg this table from the paper]). Genetically, kveik yeast strains form their own group of closely related domesticated ale strains that are a subgroup of the "Beer 1" yeasts (Belgian/Germany/UK/US yeast strains) from the [http://www.cell.com/cell/fulltext/S0092-8674(16)31071-6 Gillons/White Labs (2016)] study that sequenced previously known ale strains and found them to make up two genetically related groups called "Beer 1" and "Beer 2" (see [[Saccharomyces#History_of_Domestication|''Saccharomyces'' History of Domestication]] and [http://www.garshol.priv.no/blog/374.html "A family tree for brewer's yeast" by Lars Marius Garshol]). The closest related domesticated strains were 3 German hefeweizen strains, however, this relation is likely just due to both groups being hybrids rather than having any historic relation <ref name="Tyrawa_2017" />.
Although whole genome sequencing of more kveik strains is needed in order to fully flesh out a family tree of kveik <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/2277955402232661/?comment_id=2279696338725234&reply_comment_id=2279736462054555&comment_tracking=%7B%22tn%22%3A%22R%2321%22%7D Richard Preiss. Milk The Funk Facebook group comment about the two families of kveik yeast. 09/13/2018.]</ref>, based on the 6 strains that were analyzed, kveik strains seem to be divided into two related genetic groups, with the Muri, the Simonatis Lithuanian strain, and a Norwegian bread yeast falling outside of these two groups completely, which arguably categorizes them to not actually be considered "kveik". The two groups of kveik probably originated from two ancestors that were hybrids between a "Beer 1" yeast and wild yeast. Interestingly, the kveik cultures that have multiple strains have strains from both genetic groups of kveik. For example, Hornindal, Granvin, Laerdal, and Stordal Ebbergarden all contained strains from both genetic groups of kveik. Overall, their genetic diversity is wider than the genetic diversity of other "Beer 1" subgroups <ref name="Tyrawa_2017" />. See this [https://www.frontiersin.org/files/Articles/409253/fmicb-09-02137-HTML-r1/image_m/fmicb-09-02137-g002.jpg updated family diagram of yeast].

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