13,585
edits
Changes
added a section for wild Brettanomyces isolation
'''Wild yeast isolation''', sometimes known as "yeast wrangling", or more formally [https://en.wikipedia.org/wiki/Bioprospecting "bioprospecting"], refers to the process of catching wild yeast, and isolating it with agar plates as a pure culture. This article will also contain information on growing up a ''captured'' culture in wort rather than isolating yeast cultures on agar plates.
:''Special thanks goes out to Bryan from Sui Generis blog and Jeff Mello from Bootleg Biology for providing the information in this article.''
* The risk of botulism toxin is extremely low, but not zero. Generally, ''C. botulism'' is not able to grow and produce toxin in low protein (non-meats) substances at a pH lower than 4.6 <ref>[http://www.ingentaconnect.com/content/iafp/jfp/1982/00000045/00000003/art00005 Toxin Production by Clostridium Botulinum in Media at pH Lower Than 4.6. Nobumasa, Tanaka. Journal of Food Protection®, Number 3, February 1982, pp. 214-284, pp. 234-237(4)]</ref><ref>[http://edis.ifas.ufl.edu/fs104 Preventing Foodborne Illness: Clostridium botulinum. University of Florida IFAS Extension. Retrieved 7/5/2015.]</ref>. However, proteins in the wort may allow growth at a lower pH than 4.6 (studies have not been done on wort, only on meats) <ref name="BryanMTF"></ref>. The presence of more than 5% oxygen in the wort will also reduce the risk <ref>[http://www.ncbi.nlm.nih.gov/pubmed/15895734 Growth and toxin production by Clostridium botulinum in steamed rice aseptically packed under modified atmosphere. Kasai Y, Kimura B, Kawasaki S, Fukaya T, Sakuma K, Fujii T. May 2005.]</ref>.
* To our knowledge, there have been no documented cases of food poisoning from beer <ref name="Bryan"></ref>. However: "It is well established that at least a dozen human pathogens can survive in fully fermented beer; moreover, sour-brewing (and home brewing in general) offers an additional opportunity for pathogens to gain a foothold or produce toxins which persist into the final product. Reality is that the source of most food poisonings is never established. A few industries (milk, meat, canning, etc) are under close scrutiny, and as such we have firm numbers for rates of food-borne illnesses from those industries. Neither commercial nor homebrewing is subject to that monitoring, so any cases of disease arising from contaminated products from either source would likely go unidentified." - Bryan of Sui Generis Blog on MTF <ref name="BryanMTF"></ref>. For more information on the potential for pathogens surviving in beer, see this [http://suigenerisbrewing.blogspot.com/2014/02/fact-or-fiction-can-pathogens-survive.html Sui Generis Blog article.].
* In the words of Bryan from [http://suigenerisbrewing.blogspot.ca/2014/02/fact-or-fiction-can-pathogens-survive.html Sui Generis Blog]: "If you have an immunodeficiency or are immunosuppressed: Obviously, don't take medical advice off the internet. Talk to your MD medical doctor to see if you are at risk of infection - especially if you're condition/treatment increases your risk of fungal infections. If so, or if you are concerned, stick to beers that are fermented using commercial strains of Saccharomyces yeast." <ref name="Bryan"></ref>* See also [https://www.facebook.com/groups/MilkTheFunk/permalink/1283377785023766/ this thread on MTF].* See also [https://www.facebook.com/groups/MilkTheFunk/permalink/1447181778643365/?match=Ym90dWxpc20%3D this MTF thread on the mechanisms of botulism poisoning, and how it applies to different brewing processes].* [https://suigenerisbrewing.blogspot.com/2017/01/fact-of-fiction-can-pathogens-survive.html Further explanation of what makes microbes "pathogenic" by Bryan from Sui Generis Blog] and a related [https://www.facebook.com/groups/MilkTheFunk/permalink/1246624848699060 MTF discussion]. ==Wild ''Brettanomyces''==* [https://www.facebook.com/groups/MilkTheFunk/permalink/1620419974652877/ MTF discussion on the rare but possible isolation of wild ''Brettanomyces''.]
==See Also==
===External Resources===
====Links====
* [https://www.facebook.com/groups/MilkTheFunk/permalink/1489822481045961/ James Howat from Black Project shares his simple setup on MTF for continuous CO2 purging in order to discourage mold in wild starters.]
* [http://www.brewingscience.com/identification_key.htm Brewing Science Bacteria on LMDA (visual identification of various bacteria species on LMDA plates).]
* [http://bootlegbiology.com Bootleg Biology provides a full toolkit and materials for yeast isolation.] They also provide a [http://bootlegbiology.com/community/ community yeast bank].
* [http://suigenerisbrewing.blogspot.ca Sui Generis Blog.]
* [http://www.dhbrewingconsulting.com/culturing-instructions/ Culturing Instructions by Double Helix Brewing Consulting.]
* [http://suigenerisbrewing.blogspot.com/2014/02/fact-or-fiction-can-pathogens-survive.html "Fact or Fiction? Can Pathogens Survive in Beer?", by Sui Generis Blog.]
* [http://www.alesoftheriverwards.com/2016/04/forest-and-main-brewing-co-exploring.html "Forest and Main Brewing Co.: Exploring their indigenous culture", By Ed Coffey on Ale of the Riverwards Blog.]
* [http://www.craftcommander.com/brewing/2016/7/14/brewing-beer-with-a-sense-of-place-foraging-yeast-for-beginners "Brewing Beer With a Sense of Place - Foraging Yeast for Beginners" by Andrew "Gus" Addkison on the Craft Commander blog.]
* [http://brouwerij-chugach.com/?p=1171 "Yeast Wrangling Adventure", Brian Hall of Brouwerij Chugach blog shares wild yeast hunting techniques in the Alaskan wilderness.]
* [https://www.youtube.com/channel/UC8_kozGERzHnjVIizhnh43g/videos "Brewing Viking" home yeast lab videos on YouTube.]
====Books====
* [http://www.amazon.com/Yeast-Practical-Fermentation-Brewing-Elements/dp/0937381969 Yeast: The Practical Guide to Beer Fermentation (Brewing Elements)], by Chris White and Jamil Zainasheff.
* [http://dunham.gs.washington.edu/DunhamLabMinistats.pdf Dunham Lab Ministat Manual.]
====Videos====
<youtube>-tmbnPXZcFQ</youtube>
<youtube>y43x7nLTEPo</youtube>
<youtube>SwDjJKkuT74</youtube>
<youtube>viXPMtkTfk8</youtube>
==References==