Howto: Capture Wild Yeast

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So i've read up to page 33 of this thread and havent found what I'm looking for. So i"m just going to ask. Is there a problem with collecting wild yeast and bacteria at too cold of a temp? I talked to a rep at morebeer a while back and he said that some European brewery he went to only brewed when it was cooler to collect their yeast. So today i brewed a small .5gal batch to leave out for about 12hrs. Then i read on this thread that most people are collecting at around 50-60 degrees. Our temps here right now are between 10-30. I guess one persons idea of cool is different than anothers. Is this going to be a problem? Not that I can do anything about it now. Thanks

So 7 days later and all I have is about 6 small spots of white fuzzy mold. So i guess this time it didnt work out. Maybe the very cold temps? Is there anything I can do to salvage this project? Maybe skim the top and re expose. Out temps have warmed here. We are now getting up to about 40f during the day, WHOOO HOOO. It is only a 1/2 gal, so no big loss if not.
 
@ Turboninja64

I finally had success with leaving it out for 24 hours then dumping the contents into a flask with a wadded paper towel stopper. The warm snugly confines of the flask really let the yard yeast flourish. I put it in the pantry which stays a consistant 72 degrees. a day or two later you could really see the tiny bubbles masses you are looking for. I then went about stepping it up a couple times.

It may look as if there is no wild yeast in the outdoor container, but most assuredly there is. It just needs the right conditions to really take off.

Or maybe i just got lucky :D

Either way i have a vigorous krausen on my gallon test batch. It smells like Brett B on steroids. I cant wait.
 
This thread is amazing:mug:

I was so inspired I decided to try it out with a small wort sample. I put about 4oz of ~1.030 wort in a mason jar and set it out under my covered front porch for 2 hours or so one evening. The temperature was about 53º F. After bringing it inside I transferred the wort to a sanitized beer bottle and attached an air lock.

After a week or so I checked the bottle and there was evidence of a krausen line roughly two fingers above the water level and a nice layer of light sediment on the bottom. I stuck the bottle in the fridge to cold crash for a few days.

I decanted a bit of the beer off the top to sample. It tasted very similar to a saison yeast, not sour but a bit of tartness, spice and funk. Now that I had a ballpark category I planned out a half batch saison recipe to run as a test. I decided on a simple extract recipe to save time and effort:

Stats
OG: 1.049 SG
FG: 1.006 SG
AA: 87.1%
ABV: 5.7%
IBU: 29.4
Color: 8 SRM

Fermentables
1.5lbs - Pilsner DME
6 oz. - CaraMunich III (steeped)
8 oz. - turbinado sugar

Hops
.25 oz - Perle 9.0% AA at 60 min.
.25 oz - Perle 9.0% AA at 10 min.

I stepped up my yeast to a 600 mL starter and this is what it looked like after cold crashing and decanting:

w1w_zps206eaebd.jpg


Looks like yeast to me :rockin:

I brewed my batch a week ago today and stuck it in my old MR. BEER keg to ferment (I guess it's good for something after all). The yeast took off in about 8 hrs and started slowing down 3 days later. I was curious so I pulled a sample and the gravity was 1.006 already :drunk:

The taste was unlike anything I've tasted before. It was absolutely delicious. Very dry but with a lingering sweetness. The flavor was fruity with a noticeable estery peach flavor (the yeast was harvested in GA after all :fro: ) as well as subtle mango/tropical fruit notes. There was not really any funk to speak of and no off flavors. I can't believe I lucked out with such a flavorful yeast!

I pulled another sample this afternoon and it's still going:

w3w_zpsb4ab9835.jpg


1.004 SG. That's over 91% attenuation!

Here's what it looks like:

w2w_zpse02796a9.jpg


Still a lot of yeast in suspension, but almost all of it flocculated out with a short time in the fridge. It should end up pretty clear when it's finished.

I'm going to let it ride for a few more weeks and maybe secondary in a couple gallon jugs for a while just to make sure something else (like Brett) doesn't decide to show up. I'll be bottling so I don't want any bottle-bombs.

Any idea of a good time frame to make sure it's done?

Thanks, and sorry for the long post :mug:
 
A post I saw a couple of pages back about the use of heavily hopped wort intrigued me. Does hopping reduce the likelihood of growing mould, in addition to bacteria? Mould is the main thing that stops me from doing this more often. Also, does mould dislike acidity, and to what extent?
 
I brewed up a 3 gallon 100% wheat beer for this today and pitched the raisin yeast a couple hours ago. It has already developed a small kruasen top and is very active.

I'm looking forward to the results in a few days.

California Raisin Wild Yeast (Texas)

100% Wheat Beer
OG: 1.044
FG: 1.013

Tastes great without raspberries!

Secondary on to 48oz of raspberries today. Yeast already attacking those.

Picture pleasure attached.

Secondary Raspberry (Framboozle).jpg
 
^I love the malted wheat counter in your sig :D

Question for everyone on this thread:

In all my attempts to capture wild yeast, i have only encountered strains of Brett. Given this, i am assuming that a majority of the airborne yeast in my area is brettanomyces. Have you other yeast harvesters found any good sacc strains? should i try fruit skins instead of exposed wort? I really want to find a wild sacc yeast with some character, but not all wet horse blanket.

Thanks again!
 
I've captured wild Sacc, but I've only been interested in Brett so I've never kept any strains or tested them out. Based on my wild collections, I seem to get more Sacc (and possibly other non-Bretts) when the temp is warmer outside. Not sure if there is a real correlation since I've only done a handful of collections. It's help if you have some way to make selective plates/media or can put your yeast under a microscope.

I'll ask another question. I have 3 different wild Brett strains fermenting a simple wheat extract. They are about 2.5 months old and in the past week, 2 of them started to get really dark. I'm talking about a light wheat beer to a vary dark amber colored beer. I did a bit of searching and haven't found any answers. Anyone ever seen anything like this? I'll post pictures tomorrow.
I did sample them a few weeks back and maybe the air exposure caused some oxidation or some other reaction? I've never seen this with other beers I've brewed, but this is the first time I've done such small volumes.

Here is a photo. All started like the gallon on the right.
The color difference is not due to lighting, although all three are a bit darker due to the poor quality photo.

Any ideas?
Thanks.

20130114_162448.jpg
 
sorry i got nothing, only a question. bluedubbed (or others) what plates/selection are you using to isolate brett? i just plated girardin dregs on plates made from 1.038 wort, 1% agar, chx 25 ug/ml, chlor 50 ug/ml. the plates are clear as the blue sky after 4 days room temp.
 
Hey Dinnerstick.

The plates I use are not that much different than what you have. I use WLN (recipe here - http://www.condalab.com/pdf/1086.pdf) supplemented with 10 ug/ml chx (first few batches I used 20ug/ml and growth was a bit slower) and 25 ug/ml chlor. Maybe you want to step back the chx and chlor at bit especially since you are trying to isolate yeast from a bottle. I'm not sure though.

When I make my initial collections outside I use both chx and chlor. After I pick and streak out individual colonies I use WLN plates with just chx and bromocresol green (10ug/ml - I think, but will have to check my notes) since I'm not so worried about bacteria at this point.

I grow everything at 30 degrees C. I found that some come up overnight and others have taken 3-4 days to get sizable colonies. I also recently want back to some plates I had a 4 degrees C (for a few months) and noticed a handful of new colonies appeared. I will grow these in liquid culture to see if the morphology is different from others I've grown.

I think I've read on this thread or other blogs that people have let plates go for 3+ weeks when isolating yeast from dregs. It doesn't quite make sense to me (unless the media is really poor), but I've never tried to do this so I don't know. Sorry.

So, maybe drop the chx and chlor a bit and maybe try a more defined media vs. wort. Keep us updated.
 
thanks a lot. very helpful information. i'll try both suggestions (wln media and less drugs). i have been growing liquid cultures at 30 but plates at room temp (trying to be a bit inconspicuous at work) which i guess is ~21.
i haven't seen that 3 week plate suggestion, like you it goes against my microbiology instincts.
unfortunately i'll have to go open a new bottle. girardin or cantillon?? or oud beersel? such choices.
cheers!!
 
I've captured wild Sacc, but I've only been interested in Brett so I've never kept any strains or tested them out. Based on my wild collections, I seem to get more Sacc (and possibly other non-Bretts) when the temp is warmer outside. Not sure if there is a real correlation since I've only done a handful of collections. It's help if you have some way to make selective plates/media or can put your yeast under a microscope.

I'll ask another question. I have 3 different wild Brett strains fermenting a simple wheat extract. They are about 2.5 months old and in the past week, 2 of them started to get really dark. I'm talking about a light wheat beer to a vary dark amber colored beer. I did a bit of searching and haven't found any answers. Anyone ever seen anything like this? I'll post pictures tomorrow.
I did sample them a few weeks back and maybe the air exposure caused some oxidation or some other reaction? I've never seen this with other beers I've brewed, but this is the first time I've done such small volumes.

Here is a photo. All started like the gallon on the right.
The color difference is not due to lighting, although all three are a bit darker due to the poor quality photo.

Any ideas?
Thanks.

I have seen the opposite, going to very light. Are you sure they are Brett strains? How did you profile them?
 
thanks a lot. very helpful information. i'll try both suggestions (wln media and less drugs). i have been growing liquid cultures at 30 but plates at room temp (trying to be a bit inconspicuous at work) which i guess is ~21.
i haven't seen that 3 week plate suggestion, like you it goes against my microbiology instincts.
unfortunately i'll have to go open a new bottle. girardin or cantillon?? or oud beersel? such choices.
cheers!!

Take it very easy on the antibiotics, the cells are very weak when they are dorment and at the bottom of a bottle for a long time. Sometimes its even better to leave them out completely and go by visual inspection of colonies. 3 weeks is not absurdly long, especially for half-dead yeasts.
 
thanks a lot. very helpful information. i'll try both suggestions (wln media and less drugs). i have been growing liquid cultures at 30 but plates at room temp (trying to be a bit inconspicuous at work) which i guess is ~21.
i haven't seen that 3 week plate suggestion, like you it goes against my microbiology instincts.
unfortunately i'll have to go open a new bottle. girardin or cantillon?? or oud beersel? such choices.
cheers!!

But you are in Utrecht! You should be able to get those bottles pretty cheap and easy! ;)
 
I have seen the opposite, going to very light. Are you sure they are Brett strains? How did you profile them?

Huh, that's interesting.

I putatively identify Sacc (and maybe others?) vs Brett first by collecting everything on an agar plate with either no drugs or just antibiotic to inhibit bacterial growth. Then I streak out individual colonies on a plate with cycloheximide and bromocresol green. The Brett guys are going to be cycloheximide resistant and white to light blue in color.

I then grow them in liquid culture and look at the morphology under a microscope. I've asked a few friends that study Sacc, and they've all said 'definitely not Sacc'. I showed one to a guy that studies Brett and he agreed that it's more than likely a Brett strain.

Most of what I collect seems to be sensitive to cycloheximide and grow blue/dark blue on bromocresol green. More than the opposite. It also seems to be a bit temp and location dependent.

Sure this doesn't definitively identify these guys as Brett, but I think very few other yeast will fall into this profile. Haven't done any PCR yet, but may once I find a strain that makes a good beer that I like.

All that plusthey don't taste like a Sacc beer!

I'm not a yeast geneticist, but this is what I've gathered from talking to yeast people and doing a bit of reading of the literature.
 
Take it very easy on the antibiotics, the cells are very weak when they are dorment and at the bottom of a bottle for a long time. Sometimes its even better to leave them out completely and go by visual inspection of colonies. 3 weeks is not absurdly long, especially for half-dead yeasts.

ok, thanks for that. the last time i plated dregs i had only one plate left and (embarrassingly) no control plate, so i just spread them to see what i got. are chx/chlor even still active after 3 weeks @RT? or is early selection sufficient to weed out bugs/sacc/etc? anyways i'll do it properly next week with low drugs and -drugs.

But you are in Utrecht! You should be able to get those bottles pretty cheap and easy! ;)

yeah, i know. the things i do for this hobby.... but imagine my dilemma, even as we speak i have kriek or gueuze from 5 different breweries in my fridge... how do i choose??
 
I'm in NA - Utah. We live at about 8000 ft and most of my samplings have been in the mountains between 7-10,000 ft. Probably has something to do with what yeast I'm getting.
I'm not sure about chx, but I use chlor plates (for bacterial work) that are 5-8 months old.
Let us know what happens next time you plate.
Such a dilemma! We only get Lindemans in UT, which is great the first time you try a lambic...
It's always fun going out of state and seeing all the different lambics/sours that are available.
 
I'm in NA - Utah. We live at about 8000 ft and most of my samplings have been in the mountains between 7-10,000 ft. Probably has something to do with what yeast I'm getting.
I'm not sure about chx, but I use chlor plates (for bacterial work) that are 5-8 months old.
Let us know what happens next time you plate.
Such a dilemma! We only get Lindemans in UT, which is great the first time you try a lambic...
It's always fun going out of state and seeing all the different lambics/sours that are available.

I cannot get my hands on chx here and use ampicillin to keep bacteria at bay.
Chloramphenicol is pretty stable, you can even autoclave it I believe, and that is not the case for ampicillin for sure.
 
Hey guys I need some thoughts. I did a brew yesterday (belgian strong), and did that thing where you get tired after cleaning and left the hydro sample out and forget about it. So, just before lunch time today I noticed it had gotten a bit cloudy, poured myself a beer and left it there.

I went back tonight... and a lot of stuff was happening in there. Mini fermentation.

IMG_4890-768x1024.jpg


Now there is a chance that I had tiny amounts yeast matter left in the cylinder. I dont wash it too thoroughly between brews but it does get a decent rinse out. Even if this is this case, I would have thought it would take more than 24 hours to reach this level of fermentation from such a small amount of yeast.

I am guessing that its probably some old yeast, mixed with bugs around my garage. I have had some definite brett infection in the past. (tasted bloody good!)

Whats happened here? I am curious so poured it off into a jar and put some foil over it. I intend to see what it results in. This is another two hours later:

IMG_4894-768x1024.jpg


PS: I have since added another third clean water. OG was 1.072 afterall
 
900 replies and Im not sure if this has been covered.....

So using straight up Sacc as a fermentation source creates alcohol which theoretically is a fairly inhospitible environment for a lot (not all) pathogens. Translating this I was wondering if making up some unfermented wort as a nutrient source and dilute it with some vodka (mathematics needed here) to about 3-10% would kill a lot of the alcohol intolerant bugs whilst creating a survivable environment for the yeast that can survive in an alcoholic environment and then expose this to air and see what I get.


e.g: e-coli/shigella/salmonella is something i dont want but any wild sacc/brett/pedio/lacto I do and from a quick search on the net, all three pathogens have some form of vulnerability to alcohol.

Is that an idea? Has it been covered in this already or is it just plain dumb?
 
e.g: e-coli/shigella/salmonella is something i dont want but any wild sacc/brett/pedio/lacto I do and from a quick search on the net, all three pathogens have some form of vulnerability to alcohol.

Is that an idea? Has it been covered in this already or is it just plain dumb?

It is an idea, but I think lowering the pH to ~4.3 with some food grade acid is a safer idea. There is a lot more research on the pH required for growth of the various pathogenic microbes, and it is something that some Belgian lambic brewers (and American breweries trying spontaneous fermentation) are doing to keep things safer.
 
It is an idea, but I think lowering the pH to ~4.3 with some food grade acid is a safer idea. There is a lot more research on the pH required for growth of the various pathogenic microbes, and it is something that some Belgian lambic brewers (and American breweries trying spontaneous fermentation) are doing to keep things safer.


Good idea.... Do you know of any issues with agar plates with the pH so low?

Am gg to do some DME and citric acid to get it down.
 
Good idea.... Do you know of any issues with agar plates with the pH so low?

Am gg to do some DME and citric acid to get it down.

I haven't made an agar plate since high school. I'd assume you have fewer concerns using plates than wort as you'll be able to select which cultures you want to pitch? Maybe look into selective media: http://bkyeast.wordpress.com/experiments/
 
This thread really should be unstickied, locked and buried in a deep hole. While the first post sort of contains some facts, it's also open to misinterpretation. The following 25+ pages (that's as much as I could manage) mostly serve to lead people further astray.


Capturing and isolating yeast *is* actually fairly simple. Here's my recipe:

Prepare a wort sample, inoculate it in open air for a couple of hours or over night (or just throw in some fruit peel), then let it ferment for two weeks. The alcohol created by fermentation eventually kills off a lot of the undesireables.

If the final gravity is OK and whatever you're left with isn't too gross, now you have something to keep working with.

This is when you take samples for your petri dishes. Or you could just wash and pitch it in a starter if the remaining infections don't bother you.

Outside temperature, city pollution and whatever else is given serious weight in the first 25 pages really have very little to do with it, and yet again, I think a sticky that doesn't start off like that is in order.
 
This thread really should be unstickied, locked and buried in a deep hole. While the first post sort of contains some facts, it's also open to misinterpretation. The following 25+ pages (that's as much as I could manage) mostly serve to lead people further astray.

Capturing and isolating yeast *is* actually fairly simple. Here's my recipe:

Prepare a wort sample, inoculate it in open air for a couple of hours or over night (or just throw in some fruit peel), then let it ferment for two weeks. The alcohol created by fermentation eventually kills off a lot of the undesireables.

If the final gravity is OK and whatever you're left with isn't too gross, now you have something to keep working with.

This is when you take samples for your petri dishes. Or you could just wash and pitch it in a starter if the remaining infections don't bother you.

Outside temperature, city pollution and whatever else is given serious weight in the first 25 pages really have very little to do with it, and yet again, I think a sticky that doesn't start off like that is in order.

Wow wow easy captain. I agree there is a lot of misinformation going on but this is a popular thread. Some people are interested in isolating the strains, some people are interested in brewing with whatever falls in (consortia) and there are people who get contaminations. That all together makes a nice mix of interests and sometimes we might get a little side tracked.

Outside temperature is quite important. Gueuze breweries only brew during the colder months, because bacteria will take over if its too warm. If you want to brew spontaneous, you need to keep that in mind. Yeast will grow but you will have a nice enteric taste going on as well perhaps not the nicest.
Fruit peel does not contain a lof of yeasts, it is a big misconception. Only damaged fruit carries serious weight in yeast.

I agree that catching yeasts is quite straightforward. But I have only tried it in a handful of places and I cannot know how it will be somewhere else. And I have had my failures as well.

Perhaps you could do a nice writeup?
 
Wow wow easy captain. I agree there is a lot of misinformation going on but this is a popular thread. Some people are interested in isolating the strains, some people are interested in brewing with whatever falls in (consortia) and there are people who get contaminations. That all together makes a nice mix of interests and sometimes we might get a little side tracked.
By all means. I like the topic, but because of all the misinformation and bad practices in the first 25+ pages, which isn't people getting going off on tangents, I don't think this thread makes a decent intro to wild yeasts and should be stickied with "howto" in the subject line.

Outside temperature is quite important. Gueuze breweries only brew during the colder months, because bacteria will take over if its too warm. If you want to brew spontaneous, you need to keep that in mind.
I think I came across one reference to something along those lines. The recurring theme, though, was that high temps lead to too much mold, which makes yeast capture infeasible.

I certainly don't have all the right answers and think the people who have been keeping this thread alive would do better at starting a new sticky if that's what you're suggesting. Just keep your audience in mind; anyone without a decent lab should certainly ferment something before they bring out the agar. And not dump the jar over a little mold growth before the brewer's yeast kicks in.
 
perhaps someone can provide some advice or insight.

I Brewed what would have been a cream ale(minus typical American ale yeast) but brought the gravity up to about 1.060 in the last 10 minutes with pure maple syrup. When the boil was finished I covered the kettle with a cheese cloth, "coolshipped", and left it right where it was for about 2 days.
Then (without any visible sign of life) I decide to trust that something must have inoculated the wort. Siphoned to a carboy and air-locked it up. Within about one more day (total on day 3 since brewed) I had a small krausen forming. In 2 more days a decent 1-2" krausen and the airlock rocking. This went for about 9 days from there, bubbling hard until finally slowed down and the krausen fell about 2 days ago. Those numbers are rough estimates but today is day 15 for sure. No more krausen no more airlock activity, and I checked the gravity. 1.050?? It looked to be going so strong. Most of what I have been reading from previous posters in the thread seemed to indicate very fast fermentation. I am wondering have some experienced slow ferments? or maybe I captured a non alcohol tolerant strain? I know it isn't uncommon to let a wild beer sit a long time to fully develop its funk, but at this rate, purely from an attenuation stand point, to get down to a decent FG, it will take about another 2 months. That is if the yeast is still active, (I will check grav again monday) Any thoughts?
 
perhaps someone can provide some advice or insight.

I Brewed what would have been a cream ale(minus typical American ale yeast) but brought the gravity up to about 1.060 in the last 10 minutes with pure maple syrup. When the boil was finished I covered the kettle with a cheese cloth, "coolshipped", and left it right where it was for about 2 days.
Then (without any visible sign of life) I decide to trust that something must have inoculated the wort. Siphoned to a carboy and air-locked it up. Within about one more day (total on day 3 since brewed) I had a small krausen forming. In 2 more days a decent 1-2" krausen and the airlock rocking. This went for about 9 days from there, bubbling hard until finally slowed down and the krausen fell about 2 days ago. Those numbers are rough estimates but today is day 15 for sure. No more krausen no more airlock activity, and I checked the gravity. 1.050?? It looked to be going so strong. Most of what I have been reading from previous posters in the thread seemed to indicate very fast fermentation. I am wondering have some experienced slow ferments? or maybe I captured a non alcohol tolerant strain? I know it isn't uncommon to let a wild beer sit a long time to fully develop its funk, but at this rate, purely from an attenuation stand point, to get down to a decent FG, it will take about another 2 months. That is if the yeast is still active, (I will check grav again monday) Any thoughts?

This is not unusual. I have isolated many strains that only will ferment very briefly, and not too far down. Probably not a saccharomyces you have there being active but that is just guessing from my side. Check http://www.bjcp.org/docs/LagerYeast.pdf page 9 Diego Libkind presentation has a copy from a table showing what I mean. Good things happen to those who wait perhaps Sacch/Brett is there but just in small numbers. 2 months is not very long for a coolship inoculated beer.
 
Sounds like Kloeckera apiculata ate all the glucose from the maple syrup and then bummed out when they got to the maltose. Wait until it starts again; if there's other strains, they'll eat the dead K. apiculata and the other sugars and hopefully you'll get a nice krausen happening again. If it grows mould, start again and don't put maple syrup in until you're sure some of the maltose is being eaten. My 0.02 anyway. G'luck. :)
 
First, thanks a lot guys.

Ok so now it seems after a little more research on the info you two gave me it probably is Kloeckera? I'm in the 2 week window and down the points that would have likely been added by the maple. I checked the grav again today, it hasn't budged. This has an extremely citric/tropic odor. Orange and Mango or papaya or something I can't place exactly, and a ton of funk. So my questions now are, is there anything wrong with pitching a yeast strain (perhaps saison) to finish this thing up now rather than wait hoping sachro takes over and no mold pops up? Also if I do this do you think I will still have some definite character from the Kloeckera or would the pitched strain dominate (I realize this is probably hard to say definitively but a guess or past experience?) also if it is k- will this be able to coexist with the pitched yeast? Say I like how this turns out and harvest the yeast cake. Will some of this character make it to the next batch?
 
Hey!

I tried to find my answer in the thread but you know... after a few pages I lost the ambition...

2 weeks to get saccharomyces... really? I've seen people do only overnight and get some sort of yeast (sacch or brett..)
 
Tiroux said:
Hey!

I tried to find my answer in the thread but you know... after a few pages I lost the ambition...

2 weeks to get saccharomyces... really? I've seen people do only overnight and get some sort of yeast (sacch or brett..)

Ignore this thread and listen to the Jean Van Roy podcast on basic brewing radio.
 
First, thanks a lot guys.

Ok so now it seems after a little more research on the info you two gave me it probably is Kloeckera? I'm in the 2 week window and down the points that would have likely been added by the maple. I checked the grav again today, it hasn't budged. This has an extremely citric/tropic odor. Orange and Mango or papaya or something I can't place exactly, and a ton of funk. So my questions now are, is there anything wrong with pitching a yeast strain (perhaps saison) to finish this thing up now rather than wait hoping sachro takes over and no mold pops up? Also if I do this do you think I will still have some definite character from the Kloeckera or would the pitched strain dominate (I realize this is probably hard to say definitively but a guess or past experience?) also if it is k- will this be able to coexist with the pitched yeast? Say I like how this turns out and harvest the yeast cake. Will some of this character make it to the next batch?

That sounds like a damn interesting contribution from whatever yeast have gotten to work! Is it a yeast character you enjoy?

What I would do personally is rack the brew off the yeast onto a Saison strain (save some of it so you still have some pure Saison yeast left over), especially if you are happy with how it's turning out so far, but don't pitch too much Saison as you might scrub off the wild character with the excess carbon dioxide. Also, ferment reasonably cool (ie cooler than summer outside) so the saison character doesn't dominate too much. Save the wild cake just in case you're really happy with how the beer turns out.

That way you get some wild character, plus a good dose of yeast character you know you'll like, and if you leave it in a carboy you might end up with some brett character a year or so down the track as they eat the complex carbs.

I think pitching is definitely worthwhile as you can never be sure if you'll get Sacch activity before mould kicks in. Either way, Brett won't show up until much later and is going to do so if it's there whether or not the wort is eaten by wild or cultivated Sacch.

Another idea is to rack off the wild cake, ferment slowly with a reasonably neutral strain (or lager it!), then dryhop with a tropical/citrussy hop.

As for "coexisting", the K. has done it's job and you won't hear from it again. It's either sleeping or dying; in my experience, from the autolysis taste I get from wild brews sometimes, it's likely the latter, so the other yeast will use their corpses for nutrients. K only eat glucose/dextrose and maybe fructose and I think they conk out at around 2-3 percent abv.
 
Yup so I pitched. I'm not worried about the saison yeast I have plenty. I'm fermenting very cool for a saison strain 68. Good to know if Brett is there it will do its thing later down the line anyway. I don't know if the wild yeast that ate the first 10-12 grav points imparted a character I am going to like or not, but it definitely imparted something! the saison yeast probably won't be able to scrub it all off, it is quite pungent haha. Hopefully it just mellows it a bit. When the saison finishes up I will rack to another carboy and play the waiting game for the Brett.
 
After reading nearly all of this thread, I decided to take a stab as well. I threw some generously hopped pale ale into a couple of mason jars outside for an hour. Two days later I had what looked like to be moldy almost, little white circles. Next day, everything was all foamy, almost krausen-like. No real off smell to it. If I can find the chord I'll up some pictures.
 
After reading nearly all of this thread, I decided to take a stab as well. I threw some generously hopped pale ale into a couple of mason jars outside for an hour. Two days later I had what looked like to be moldy almost, little white circles. Next day, everything was all foamy, almost krausen-like. No real off smell to it. If I can find the chord I'll up some pictures.

Mould is not good. I hope you skimmed it off.
 
Oh, COLO,
I don't know why I didn't think of this earlier -- there is a way to get to a pure culture without solid media if you have a lot of sterile containers. It is called limiting dilutions. The idea is to dilute a culture enough times that only single cells remain.

You will need a bunch of tubes or containers about the size of the tubes you would use to make slants. And you will need something to move your culture/fresh wort around. A pipette with sterile tips is perfect. A bunch of sanitized metal spoons will work too.

The procedure is to take a drop of the most recent mixed wild culture and dilute it into 9 drops of fresh wort. If you're using a pipette, dilute 100 micro Liters into 1 mL. Either way, you have diluted the culture 1 to 10.

Now repeat this 10-fold dilution several times, each time taking a drop of the diluted wort from the previous step and diluting it further into 9 drops of fresh wort. Use a fresh pipette tip / sanitized spoon for each dilution.

Let's say, for example, you started with 1000 cells in your tube. After one dilution, you have 100 cells per tube. After two dilutions, you have 10 per tube. After three dilutions you have just one cell per tube. After four dilutions, you'd have -- either one cell or none at all. This is the level of dilution you want to get to, where most of the tubes don't contain any cells. At this level of dilution, you know that any tube that DOES grow, started from just one cell. This will get you to a pure culture!

But how many dilutions are requried? You're starting with more than 1000 cells, so it will take more than four dilutions, but not too many more. A White Labs tube is extremely dense with yeast, and it is about a billion cells per mL. A billion is 10^9. So, if you do 9, or let's be safe and say 10 of these 10-fold dilutions in a series on your culture, you should already be in the zone.

Let's say you find that all the dilutions starting with the sixth don't grow anything. Now, go back to the undiluted culture and do the 10-fold dilution six times, but make a bunch of tubes of that sixth dilution. Make 20 or so. You already know that most of them will not grow. But a few will grow, and you will know they started with just one cell.

Cells have a tough time growing by themselves, so make sure you keep the volume small, 1 mL at the most, aerate every day, and give the cultures plenty of time to grow. It might take a few weeks of aerating every day before the most extreme dilutions show signs of growth.

This is a lot of work, and I have only read about it, not tried it. But limiting dilution it is a standard microbiology technique and it will work! You may prefer to just buy some sterile plastic plates and agar, though. :eek:

drummstikk,

I think this is the most solid way to get a pure culture that I've read in this thread. Question though - When you sample the wild culture, would you do that immediately after you saw the most yeast activity? Around 2 weeks or so? Maybe even take some of the yeast from the bottom and create a new starter with that. Then sample from that starter? Would that help to ensure that the cell count of yeast is the highest compared to cell count of other microbes? Unless I am interpreting the way other microbes replicate, I'd rather not go through all this trouble only to end up with a pure culture of a microbe I didn't want to begin with.
 
Since this thread keeps getting bumped, I'm just wondering... After 4 years and 919 posts, has anyone pointed out that the basis of this thread is a misinterpretation of Guinard as referring to inoculation, when he is actually referring to fermentation?
 
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