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added section "Notes on Fermentation Timeframes"
* Monitor for mold growth. If mold begins to grow on the growth media, scrape it out and continue on with the isolation process. This should be safe since isolating the yeast will separate it from any potential mycotoxins that developed during the initial catching. Do not consume any growth media that has had mold grow on it (see [[Mold]]).
* In general, summer and spring are more successful times to catch wild yeast, however any time of year can be successful. Simply choose fruits or flowers that bloom/grow during that particular season. For example, in spring, flowers and fruit blossoms are a good source. In summer, wild summer fruit can be a good source (raspberries, strawberries, cherries, etc.). In the fall, apples and grapes can be a good source. In winter, juniper berries <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1683379841690223/?comment_id=1683799054981635&comment_tracking=%7B%22tn%22%3A%22R%22%7D Milk The Funk thread on the best seasons for bioprospecting. 05/11/2017.]</ref>.
* A new study showed that wild yeast actually exists more so in leaf matter on the ground than it does on bark or fruit. See the [[Wild_Yeast_Isolation#Videos|"Where (Do) the Wild Yeast Roam" video by Bryan from Sui Generis blog]] below.
* [https://www.facebook.com/groups/MilkTheFunk/permalink/1034954619866085/ David Thornton's use of foam as stoppers.]
===Isolating===
* [http://suigenerisbrewing.blogspot.ca/2014/12/two-new-videos.html Sui Generis Blog] video guide on streaking plates and further isolating yeast.
* [http://basementbrewlab.com/lab/lab-media/sla/ Selecting for and isolating for ''Lactobacillus'' using Rogosa SL Agar.]
* [https://www.facebook.com/groups/MilkTheFunk/permalink/1713165188711688/ MTF thread with tips on isolating and growing from a single colony.]
===Identifying===
* [http://suigenerisbrewing.blogspot.ca/2014/12/new-video.html Sui Generis Blog] video guide on how to visually identify usable yeasts versus potential pathogens and molds on agar plates.
* Microbes cannot be accurately identified based on what their pellicle looks like. See [[Pellicle#Pellicle_Appearance_as_a_Microbe_Identifying_Indicator|Pellicle]] for more information.
===Growing and Testing===
==Growing and Testing Without Plating==
While using agar plates to isolate yeast colonies is the most effective way to culture wild yeast, it is not the only way. Wild yeast should first be caught using DME wort as outlined in [http://bootlegbiology.com/diy/capturing-yeast/ Bootleg Biology's ''Method 1'' or ''Method 2'']. Hopping the wort will help decrease bacteria if that is desired. The wort's pH should be lowered to 4.5 or lower with lactic acid to avoid bacteria as much as possible. Molds may still grow in the yeast starter even with the lower pH; wort that has grown mold should not be consumed because mycotoxins can contaminate the wort (see [[Mold]]). Keeping the foraged fruit, flowers, etc. under the surface of the wort will help reduce the chances of mold growth. Some brewers recommend submerging the fruit/flowers in the wort for a few minutes and then removing them to prevent them from attracting mold growth <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1659565197405021/?comment_id=1711116612249879&comment_tracking=%7B%22tn%22%3A%22R%22%7D Jeff Porn. Milk The Funk Facebook group. 06/06/2017.]</ref>. If the yeast cannot be isolated separated from wort that mold grew on then it should be thrown out. Signs of a small krausen within 1-3 days is a good sign that viable wild yeast has been collected. After another few days, the yeast will start dropping to the bottom of the collection vessel <ref name="manoaction">[http://www.homebrewtalk.com/collecting-wild-yeast.html Collecting Wild Yeast. Manoaction. Homebrewtalk. Oct 30, 2012.]</ref>.
Once the wort has fermented out (allowing 2 weeks total is a good rule of thumb), decant the beer and pitch the collected yeast into 500ml of starter wort, again lowering the pH of the starter wort to 4.5 with lactic acid. After the starter wort has been fermented, the yeast should have enough of a population to ferment out a 1 gallon batch of wort. Keep the recipe of the wort simple, and in the 1.050 gravity range. The yeast cell count should be high enough at this point to out-compete bacteria and lower the pH of the wort within a few days. The pH of the 1 gallon batch, therefore, does not need to be lowered, although the brewer may choose to do so anyway. For [[Wild_Yeast_Isolation#Safety|safety reasons]], test to make sure that the beer fully attenuated and has a pH of 4.5 or less. Allow for one month after fermenting the 1 gallon batch of beer before sampling. If it smells like feces or vomit, do not sample it and throw it away. If the beer smells ok, feel free to sample the beer to see if the wild yeast produced a good tasting beer. David Thornton from [[SouthYeast Labs]] estimates that only about 10% of yeast that can fully attenuate produces favorable results, so failures are to be expected (keep trying!) <ref name="Thornton"></ref>. Fermenting a few batches of beer at different temperatures is a useful method for identifying the ideal fermentation temperature range for the yeast.
See also:* See [https://www.facebook.com/groups/MilkTheFunk/permalink/1676671082361099/ advice from DeWayne Schaaf and others on bioproescting bioprospecting techniques without isolating microbes on MTF].
* See [[Mold]] for identifying mold and safety issues with mold. * Microbes cannot be accurately identified based on what their pellicle looks like. See [[Pellicle#Pellicle_Appearance_as_a_Microbe_Identifying_Indicator|Pellicle]] for more information. ===Notes on Fermentation Timeframes===Some wild captures might take a long time to ferment. Most wild caught, non-isolated cultures that can ferment the sugars in wort take 2-4 weeks to ferment, although some can take longer and some can take less time (even just a couple of days). This is impossible to predict due to the impossibility of predicting what microbes are in a non-isolated wild culture. For example, wild ''Brettanomyces'' might take a long time to finish fermenting (up to 8 months to reach a stable gravity, according to Matt Spaanem). In some experiences, krausen will form for a few days, and then drop, and then form again (presumably as another microbe starts fermenting). Others ferment long and slow over a month or so. Once re-pitched with higher cell counts, often the fermentation times will hasten, but other times they will not. The best piece of advice is to take gravity readings to determine when the fermentation is finished instead of relying on visual indicators. Even though there could be a krausen and signs of fermentation, if the fermentation is going slow then it is possible that the sugars in the wort are not being fermented effectively (this might improve upon re-pitching as this should help select for microbes that can withstand this environment; see reference for more details on MTF members' experiences) <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1777108328984040/ DeWayne Schaaf, Christophe Boebion, Tobias Häberli, Justin Amaral, Bryan from Sui Generis blog, Matt Spaanem, Josh Regenold, Guy Greenhalgh, Jason Pallett, Caroline Whalen Taggart. Milk The Facebook group on how long fermetnation takes for wild caught cultures. 08/01/2017.]</ref>.
===Safety===
* See also [https://www.facebook.com/groups/MilkTheFunk/permalink/1447181778643365/?match=Ym90dWxpc20%3D this MTF thread on the mechanisms of botulism poisoning, and how it applies to different brewing processes].
* [https://suigenerisbrewing.blogspot.com/2017/01/fact-of-fiction-can-pathogens-survive.html Further explanation of what makes microbes "pathogenic" by Bryan from Sui Generis Blog] and a related [https://www.facebook.com/groups/MilkTheFunk/permalink/1246624848699060 MTF discussion].
* If mold grows on growth media and the yeast can be isolated cleanly, then this is not an issue, however do not consume beer or wort that has had mold growing on it. If the yeast is not being isolated on agar plates, then throw out the capture sample and do not use it. See [[Mold]] for identifying mold and safety issues with mold.
==Wild ''Brettanomyces''==
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==References==