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* MRS media and some other media types are not food grade, and should only be used for initial propagation from frozen stocks (and afterwards decanted or pelleted) or for making agar for isolation. MRS media should not be used for large propagation such as starters or yeast propagators at breweries <ref>Nick Impellitteri. Private correspondence with Dan Pixley. 03/23/2020.</ref>.
* Richard Preiss from [[Escarpment Laboratories]] reported better agar results when limiting autoclave times to 15 minutes for recipes that include copper-containing ingredients <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/2874530432575152/?comment_id=2874872599207602&reply_comment_id=2874886849206177&comment_tracking=%7B%22tn%22%3A%22R%22%7D Richard Preiss. Milk The Funk Facebook group thread about making agar. 08/27/2019.]</ref>.
* Cycloheximide will inhibit ''Saccharomyces'' and ''Brettanomyces'' at 100µg/ml <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/4744159795612197/?comment_id=4744240825604094 Christophe Pichon. Milk The Funk Facebook post regarding acetic acid bacteria isolation. 06/30/2021.]</ref>.
See also:
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'''Escarpment CSSM''' (A modified version of the Omega LCYM Media. This media is specifically for detecting [[Saccharomyces#Diastatic_strains_of_Saccharomyces_cerevisiae|diastatic strains of ''S. cerevisiae'']]; Also reported to culture beer strains of ''Brettanomyces'', ''Pichia'', and other wild yeasts <ref>[https://www.facebook.com/groups/MilkTheFunk/posts/5844925622202270/?comment_id=5852798014748364 Shawn Savuto. Milk The Funk Facebook group post on Escarpment Labs CSSM. 05/05/2022.]</ref> - see [https://cdn.shopify.com/s/files/1/0323/8825/1780/files/TQ-58-2-0611-01_1.pdf?v=1631327125 this MBAA paper].)
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===''Brettanomyces''===
A few different media can be used to isolate ''[[Brettanomyces]]'' but DBDM medium is commonly used. WLD with additions of cycloheximide can also be used. A simple Malt agar with cycloheximide has been shown to grow ''Brettanomyces'' that has been adapted to the brewing environment more efficiently than Dekkera medium (recommended by the European Brewing Convention, but not listed here) and [https://foodsafety.neogen.com/pdf/acumedia_pi/7574_pi.pdf universal beer medium] (recommended by the Brewery Convention of Japan; also not listed here) <ref>[https://www.tandfonline.com/doi/abs/10.1094/ASBCJ-2008-0917-01 Effects of Beer Adaptation on Culturability of Beer-Spoilage Dekkera/Brettanomyces Yeasts. Koji Suzuki, Shizuka Asano, Kazumaru Iijima, Tomoo Ogata, Yasushi Kitagawa & Tsunehiro Ikeda. 2018.]</ref>. DBDM may not allow all strains of ''Brettanomyces'' to grow <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/2538786349482897/?comment_id=2538810702813795&reply_comment_id=2538942496133949&comment_tracking=%7B%22tn%22%3A%22R1%22%7D Richard Preiss. Milk The Funk Facebook group thread on DBDM medium. 03/01/2019.]</ref>. The [https://cdn.shopify.com/s/files/1/0323/8825/1780/files/TQ-58-2-0611-01_1.pdf?v=1631327125 Escarpment CSSM media] for diastatic ''S. cerevisiae'' is reported to also be a good growth medium for beer strains of ''Brettanomyces'' (see [[Laboratory_Techniques#Saccharomyces|''Saccharomyces'']] above).
Renouf et al. (2007) and Comitini et al. (2019) demonstrated that an "enrichment ''Brettanomyces bruxellensis''" media called EBB is more efficient at first growing up ''Brettanomyces'' before trying to culture it on DBDM. ''Brettanomyces'' was allowed to grow for 80 days in the EBB media, and then streaked onto DBDM for selection for ''Brettanomyces'' (other wild yeast such as ''Hanseniaspora'' and ''Pichia'' grew much more readily than ''Brettanomyces'' that was cultured from wine grapes) <ref>[https://www.sciencedirect.com/science/article/pii/S0944501306000231?via%3Dihub Development of an enrichment medium to detect Dekkera/Brettanomyces bruxellensis, a spoilage wine yeast, on the surface of grape berries. Vincent Renouf, Aline Lonvaud-Funel. 2007. DOI: https://doi.org/10.1016/j.micres.2006.02.006.]</ref><ref>[https://www.frontiersin.org/articles/10.3389/fmicb.2019.00415/abstract Occurrence of Brettanomyces bruxellensis on grape berries and in related winemaking cellar. Francesca Comitini1, Lucia Oro, Laura Canonico, Valentina Marinelli, Maurizio Ciani. 2019. DOI: 10.3389/fmicb.2019.00415.]</ref>.
See also: [[Wild_Yeast_Isolation#Wild_Brettanomyces|Wild Isolation of ''Brettanomyces'']].
'''YPD'''
See [https://suigenerisbrewing.com/index.php/2022/11/02/this-is-the-wild-brettanomyces-your-are-looking-for/ this article] by Dr. Bryan Heit on using a modified YPD media that is cheaper and easier to prepare than WLN, along with techniques to help improve the chances of culturing wild ''Brettanomyces'' while mostly eliminating other yeasts and mold.
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! Chemical !! Usage Amount
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| Yeast Extract || 10 grams
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| Peptone || 20 grams
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| Dextrose || 20 grams
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| Agar(optional) || 15 grams
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| Distilled Water || Fill to 1000 ML
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'''EBB Media Recipe'''
: <youtube height="200" width="300">YMDw6xj1uvo</youtube>
* [https://www.masterbrewerspodcast.com/239 "Yeast Propagation at Urban Chestnut" interview with Florian Kuplent of Urban Chestnut on MBAA Podcast episode #239.]
* [https://www.themadfermentationist.com/2022/11/small-craft-brewery-yeast-management.html "Small Craft Brewery Yeast Management," by Michael Tonsmeire.]
Various other tips:
* When propagating yeast in an Erlenmeyer flask, use a flask that allows for plenty of headspace. This allows for a thinner layer of foam and thus more oxygen diffusion. Set the stir plate or shaker to the highest speed that doesn't produce a lot of foam. A good general rule of thumb is to use a flask that allows for 20-33% starter volume and 66-80% headspace (ideally 20% starter volume and 80% headspace). For example, for a 1L starter, use a 3L, 4L, or 5L flask (ideally 5L). More volume can be used with a Fernbach or a baffled flask, but these require a shaker table. When propagating yeast for use in beer, use wort and a magnesium and zinc nutrient for best yeast propagation practices. Cover the flask with foil (or [https://www.facebook.com/groups/MilkTheFunk/permalink/1034954619866085/ foam stoppers] if fruit flies are a problem) <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1986378521390352/ Various MTF members. Milk The Funk Facebook thread started by Jon Stanley on Erlenmeyer flask usage for yeast starters. 02/12/2018.]</ref>.
===External Resources===
* [https://journals.asm.org/doi/pdf/10.1128/jmbe.00336-21 Bootleg Biology: a Semester-Long CURE Using Wild Yeast to Brew Beer.]
* [https://www.brewerspublications.com/products/yeast-the-practical-guide-to-beer-fermentation "Yeast: The Practical Guide to Beer Fermentation," by: Chris White and Jamil Zainasheff.]
* [http://traffic.libsyn.com/basicbrewing/bbr07-27-17homelab01.mp3 BasicBrewing interview with Zack Taggart, lab manager at 42 North Brewing, on how to set up our own homebrew lab to analyze yeast health and count cell population (part 1)] and [http://traffic.libsyn.com/basicbrewing/bbr08-17-17homelab02.mp3 isolating, propagating, and storing yeast and bacteria (part 2)].