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Brettanomyces Storage Survival Experiment

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File:Trent Brett Storage Figure5.jpg|'''Figure 5''' Example of dilution plating, MYPG at room temperature. Dilutions included; left 1:10000, center 1:1000, and right 1:100.
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==Preliminary Work on 30 Day Storage==
Some preliminary work has been done by Mark Trent and Richard Preiss to examine the effects of storing ''Brettanomyces'' in MYPG and wort at refrigeration temperatures versus room temperatures for 30 days. This work suggested that cold storage for as long as one month is better than room temperature storage for the same time. Chad Yakobson also 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]]]
 
[[File:Brett storage MarkTrent.jpg|thumb|300px|[https://www.facebook.com/groups/MilkTheFunk/permalink/1115768398451373/?comment_id=1145139948847551&offset=0&total_comments=69&comment_tracking=%7B%22tn%22%3A%22R9%22%7D Mark Trent repeated Richard Preiss's results of storing Brett at different temperatures, and also in different mediums.]]]
 
Yakobson's observations were not scientifically quantified and details of his process are lacking (how was the ''Brettanomyces'' stored?), as far as we know. Richard Preiss of [http://www.escarpmentlabs.com/ Escarpment Labs] shared the results of a controlled experiment on MTF that showed that BSI's ''Brettanomyces bruxellensis Drie'' and WLP645 ''B. claussenii'' survived better in low ABV beer when stored at refrigeration temperatures rather than room temperatures for one month. 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 ''Brettanomyces'' 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>.
 
Mark Trent repeated Richard Preiss's experiment, but tested different mediums (wort, liquid MYPG, and water). Two ''Brettanomyces'' isolates, one from Orval and one from SARA Bernice, were grown in 10 degree Plato wort and MYPG. The isolates are labeled on the chart as "Brett O (Orval)" and "Brett T (Tim Clifford)" respectively. After growth was complete, 10 mL of aliquots were aseptically transferred to 15 mL centrifuge tubes. In addition, the Orval isolate was grown on a MYPG plate and 3 single colonies for each treatment were transferred to 1 mL of sterile RO water in a 2 mL glass tube. Each treatment was prepared in a duplicate and stored at either 22°C or 1°C. Viability was measured after 31 days. Data shown in the chart to the right. No other statistics were performed (there were no statistically significant differences between the different types of storage mediums at room temperature). All storage mediums shared results similar to Richard's results <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1115768398451373/?comment_id=1145139948847551&offset=0&total_comments=69&comment_tracking=%7B%22tn%22%3A%22R9%22%7D Conversation with Mark Trent on MTF. 09/10/2015.]</ref>. It appears from these experiments that ''Brettanomyces'' stores better cold when stored for less than a month, however these results need to be verified and more strains should be examined before broad statements can be applied about the effects of temperature when storing ''Brettanomyces'' in wort or MYPG.
==See Also==

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