Changes

Long term storage of ''Brett'' should be frozen with glycerol, rather than agar plates or slants, which have been observed anecdotally to reduce viability of ''Brett'' over time <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>. Chad Yakobson noted that after storing ''Brett'' in a refrigerated environment (agar plates or slants?), after 6 months the ''Brett'' would die. If ''Brett'' is stored cold, it will be very sluggish and slow to start fermentation. Non-pure cultures (such as beer bottle dregs with ''Brett'' in it) should be stored refrigerated. Making a starter is highly recommended if the ''Brett'' 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>.

Yakobson's observations were not scientifically quantified and details of his process are lacking (how was the ''Brett'' stored?), as far as we know. Richard Preiss of [http://www.escarpmentlabs.com/ Escarpment Yeast Labs] shared the results of a controlled experiment on MTF that showed that BSI's ''Brett brux Drie'' and ''B. claussenii'' survived better in low ABV beer when stored at refrigeration temperatures rather than room temperatures, contradicting the anecdotal observations reported by Yakobson. The samples were grown in 1.040 DME wort until typical cell density was reached, and measured for >95% viability after growth with trypan blue stain and microscopy. 10ml samples of each were stored in sterile conical tubes for one month at different temperatures (4°C and 24°C). The samples were burped to avoid having head pressure as a variable. Trypan blue stain and microscopy were used to measure the viability after one month. After one month of storage at 4°C (39.2°F), the viability of ''B. claussenii'' was 92%, and BSI Drie was 72% viability. The samples stored for one month at 24°C (75.2°F) showed a significant drop in viability, with ''B. claussenii'' ending up at 40% and BSI Drie at 6% viability. This experiment also indicates that the viability of ''Brett'' strains/species after storage is strain/species dependent <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1115768398451373/ Richard Preiss Brett storage experiment results on MTF. 7/24/2015.]</ref>.

Questions raised by MTF members in regards to these results:

# How does warm storage versus cold storage affect agar plates and slants?

# Are there any unexpected results if the samples are stored longer (Richard will update), and would this change if the ''Brett'' is periodically fed new sugars?

===Tips From Brewers===