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updated to link to Mark Trent's new data on 6 month storage of Brett at cold vs room temp and MYPG vs wort
Major yeast labs will often freeze yeast in liquid nitrogen using cryopreservation, however this option is generally not practical for brewers <ref>[https://books.google.com/books?id=gcJQAwAAQBAJ&pg=PA181&lpg=PA181&dq=Yeast+supply%E2%80%94the+challenge+of+zero+defects&source=bl&ots=u-9uoIvsFo&sig=XnqR3179u4mC9LqWotMX3Fu7MbU&hl=en&sa=X&ved=0ahUKEwiX-bKyvM_JAhVH4WMKHQr9C1cQ6AEIHTAA#v=onepage&q=liquid%20nitrogen&f=false Brewing: New Technologies. Charlie Bamforth. 2006. Pg 170.]</ref>. The next best option for long term storage of ''Brettanomyces'' is freezing with 10% glycerol. If glycerol usage is not an option for the brewer, then slants can provide storage for a few months up to 2+ years, depending on the type of slant used (using mineral oil in slants has been shown to extend the life of stored yeast). For instructions on how to make slants at home capable of storing any microbe for potentially 2+ years, [http://suigenerisbrewing.blogspot.com/2015/11/easy-home-yeast-banking-and-video.html see Bryan's video on Sui Generis Brewing (requires a pressure cooker)]. Agar plates are the least best solution and have been observed anecdotally to reduce viability of ''Brettanomyces'' over a few months <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1083075848387295/?comment_id=1083272091701004&offset=0&total_comments=13&comment_tracking=%7B%22tn%22%3A%22R0%22%7D Conversation with Matt Humbard, Ritchie Preiss, and Jeff Melo on MTF. 6/4/2015.]</ref><ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1115768398451373/?comment_id=1115817201779826&offset=0&total_comments=34&comment_tracking=%7B%22tn%22%3A%22R9%22%7D Conversation with Nick Impellitteri on MTF regarding storing Brett on agar plates. 7/24/2015.]</ref>.
Regarding temperature, it has been shown that cold storage for as long as a month is better than room temperature storage for the same time. The optimal temperature storage periods of time longer than a month are not known. Chad Yakobson noted that after storing ''Brettanomyces'' in a refrigerated environment (we don't know how Chad was storing the ''Brettanomyces'' cultures when he observed this, for example on agar plates or slants or something else.), after 6 months the ''Brettanomyces'' would die. If ''Brettanomyces'' is stored cold, it will be very sluggish and slow to start fermentation. Non-pure cultures (such as beer bottle dregs with ''Brettanomyces'' in it) should be stored refrigerated. Making a starter is highly recommended if the ''Brettanomyces'' culture has been stored cold <ref>[http://youtu.be/AjVOzBtE27Y?t=43m Yakobson, Chad. Presentation at 2012 Music City Brew Off. At 43:00.]</ref>.
[[File:Brett viability temp storage.jpg|thumb|300px|[https://www.facebook.com/groups/MilkTheFunk/permalink/1115768398451373/ Richard Preiss's results of storing Brett at different temperatures]]]
Questions raised by MTF members in regards to these results:
# How does warm storage versus cold storage affect slants?
# Are there any unexpected results if the samples are stored longer (Richard will update), and would this change if the ''Brettanomyces'' is periodically fed new sugars? ''Update: new information on storing Brettanomyces for 6 months at cold vs room temperatures and MYPG vs wort in this [https://www.facebook.com/groups/MilkTheFunk/permalink/1239775039384041/ MTF thread] from Mark Trent. This data appears to show that at 6 months Brettanomcyes survives better in room temperature MYPG vs cold temperature MYPG or cold/room temperature wort. pH may have an effect as well, but more investigation is needed.''
# How come using dregs from commercial beers stored at room temperature gives good results for brewers?