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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:
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.
{| class="wikitable"
|-
! Chemical !! Usage Amount
|-
| Yeast Extract || 10 grams
|-
| Peptone || 20 grams
|-
| Dextrose || 20 grams
|-
| Agar(optional) || 15 grams
|-
| Distilled Water || Fill to 1000 ML
|}
'''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)].