Howto: Capture Wild Yeast

jaredkent said:

I recently decided to try catching wild yeast based on this thread. I only had a very little amount of DME on hand, which gave me a very low OG. After 1 week though I've seen growth, and the jar smells yeasty. I'll let it sit another week, but what's the best way to help the yeast grow. Should I make a starter after the 2 weeks? It's only about a cup of wort, what size starter should I make? If I don't plan on using this yeast right away is there a way to save it? Washing it?

Any help would be greatly appreciated.

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Sure, go for it, you can move forward if it smells yeasty and seems to be fermenting. You could bump it to 2 liters, and then later go to 5 gallon or so. Adding a little bit of hops during the DME boil creates a slight anti-bacterial effect, in your 2 L. Also keeping the SG low is good for keeping the bacteria out in the beginning, but it would be good to give the yeast something to chew on so they can outcompete the rest of the bugs in there, maybe bump it to 1020-30 or so for the 2L. Rich yeast media in the lab is 1020.

For storage I would suggest putting it in an sterile (wash with boiling water, let cool) container and set it in the fridge airtight. Note, this is a live culture, so it will keep on doing its thing. Some of the yeast might be less active at this temp, and something what you dont want might be more active. dont know how long it keeps, but its probably similar to a barn for bread. Use a plastic container if you can, just so it does not pop. There is probably people here with more experience, please chime in if you read this and have a better idea.

For storage, you could also add glycerol (also called glycerin in stores) to ~25% concentration and freeze it, the glycerin keeps the cells intact by inhibiting ice crystal formation. I do this on a regular basis with pure yeast cultures, but have never done this with a mix. Should work as well.

A difference between bacteria and yeast is that yeast cells are much larger. One trick I do to quickly gage if I have no bacteria is the following,
I take a little culture out, mix it up so its a suspension, put it in a little container and set it in the fridge (say shotglass or so.) Due to the size,
the yeast will fall out faster and due to the smaller size and "swimming" the bacteria will stay much longer in suspension. if you see a clear area of liquid at the top of the glass after an hour , and whitish cells on the bottom of the glass, its a good sign (sign, not proof. Also if it does not clear it might still be good)

Hope this helps,

Jaapie

Hi,
What a thread!

I live 30KM away from Brussels. But it is more or less possible to invite Brett In your brew anywhere you are. The problem remains that you never really know what ended up in your brew.
Major issue is: I want yeasts, but no bacteria.

This is how I proceed.
In belgium, the best period to avoid infection is from october to March.
Never try this in warm weather conditions. Cold temps ans dry weather, this is key. If you want to compare teperature, it is more or less equal to NY.

Just allow your wort to cool down outside (I prefer winter nights, as the temperatures are even colder). To avoid MDS and known off flavors to develop, try to have a large surface to speed up things. One night is more than enough. Cover enough to avoid insects to dive into your wort (gaze,...).

Then, rack and be patient.
The smell is NEVER interesting in the starting phase. Well, it only gets better after months (I would say at least one year).

For best results, you need to use 50% of unmalted wheat.
you also need to use 1 year old hops (or more), stored at room temp.

Again, I would not try to bottle it before one year. And 6 months in bottle looks a minimum for a great result.

Well, you can rack in an oak barrel with cherries, but this is another story !!

I'll try next year.

have fun and treat Bretts well

Leyon

@jaapie:

Major kudos on the cabbage thing. I use things like they to pique my kidlets interest in science (gambling for math heheh) so she doesn't inherit my wifes weaknesses. Would do it via phone but can't find a + in the current ui.

I tried the wort in jars method and got quite a bit of mold even with Citric Acid added. I may have captured some wild yeast too, but I was too concerned about the mold I dumped them.

However, I'm doing a Berliner Weisse and I tried getting Lactobacillus from some grain (and it worked!). However, I also noticed that I was getting some fermentation in my Lacto culture ... so I split the batch into 2 carboys, and pitched the lacto/yeast starter in both. The next day (to give the lacto a head start) I added dry yeast to the one which had less activity. We'll see what turns out! The sample I had from the starter was tart and good!

I had better luck bringing the sample to 5% abv with vodka. Kept bacteria at bay and only got mold once and that was minor. I got some rough looking cells that way but the streaked healthy. I'm wondering if acid washing would kill off the mutants.

I want to add that also instead of lowering the sugar content, one can up it to 30-40%. Yeasts often grow on media with sugar concentrations high enough to inhibit bacterial growth. Osmotolerant molds are however not inhibited. you could scoop the mold off, and take a little of the yeast/whatever else with a pasteur pipette and drip it in a new, sterile container containing medium, to get rid of the mold (or plate).

One should also indeed acidify a little to say pH 4.5, that enhances the selectivity.

Whew, started reading this thread several days ago and figured I needed to end it to post.

I made 1 batch of beer, but just not my thing. I do like making cider and wine, though.

Lately I've been making cider with commercial apple juice and enjoying it. I'm going to try using that plain juice with wild yeasts because it will be easy to tell where flavors are coming from.

Several days ago, as I started reading this, I took 6 crabapples of my tree in the front yard. They all had a nice dry powder on them. I made a sugar water mix in a sanitized glass, added a pinch of nutrient and dropped in the crab apples. Covered it with aluminum foil and left it in the kitchen. If I do it again, I'll probably just use juice for my starter, but I'll see this through and find out what I end up with.

I currently have a milky cup of water with a barely sour smell and a stronger yeast odor. I do have two very tiny clear floating specks. I'll give it a while. If it looks good I'll pitch it, if it doesn't, I'll toss it. An easy aspect of my method is that I have a gallon of clean, pasteurized "wort" I bought for $5 today patiently waiting safe from contamination 'til I'm ready to pitch something.

Well, still about the same in the first sample I started. Except that I've got a small mold culture on the side of the glass. Also, no sediment in the bottom and very few bubbles if any. I'll leave it for a while and see if the yeast pick up. A couple weeks seems standard.

A couple nights ago I tossed some crab apples into apple juice. Nothing yet, except a very small dusting of something in the bottom of the glass. I'm optimistic that the acidity (and a couple extra nutrients) will make for a quicker show.

Just for kicks I am making an attempt at the moment. I microwaved/ boiled
about 6 oz of an IPA and added roughly about 12 oz of canned pineapple
juice and combined them in a sanitized powerade bottle. I left it outside
yesterday for a couple hours at about 50 degrees. Today I uncapped it
and set it outside for about an hour at 60 degrees. Who knows, maybe I
get something?

I wonder? if bread makers use flour/water/citric acid and do not have much
problems with mold or bacteria capturing their yeast if there is a chemical
reaction reason behind it and can we apply that here?

HatchetJack said:

Just for kicks I am making an attempt at the moment. I microwaved/ boiled
about 6 oz of an IPA and added roughly about 12 oz of canned pineapple
juice and combined them in a sanitized powerade bottle. I left it outside
yesterday for a couple hours at about 50 degrees. Today I uncapped it
and set it outside for about an hour at 60 degrees. Who knows, maybe I
get something?

I wonder? if bread makers use flour/water/citric acid and do not have much
problems with mold or bacteria capturing their yeast if there is a chemical
reaction reason behind it and can we apply that here?

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Sure the same principles apply. I know that bakers get their sourdough yeasts in this way, but beware, a lot of those yeasts do not ferment maltose, but thrive on other sugars. If you are not using malt extract, you are basically selecting for organisms which ferment - and/or use another sugar - as carbon/energy source. I do not know the maltose levels in pineapple juice, but I can imagine it being close to zero. Sticking as close to the medium you want the organisms to be in - wort - would be the way to go in my opinion.

Yeah that makes sense. What if I boiled a 12 oz IPA along with some dme
to sweeten it up. And would a splash of pineapple or lemon juice be a good or
bad addition. Would the citric acid in those work along with the hops to help
discourage bacteria or mold?

HatchetJack said:

Yeah that makes sense. What if I boiled a 12 oz IPA along with some dme
to sweeten it up. And would a splash of pineapple or lemon juice be a good or
bad addition. Would the citric acid in those work along with the hops to help
discourage bacteria or mold?

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the pH would be lowered by the (unsweetened) pineapple juice and/or lemon juice. Citric acid is probably the main acid in both, or at least it is the one in lemon juice. Adding that on top would make no difference in theory then, at least if you add enough of the former to lower it to the level you want.
Lowering the pH definitely is a good idea to give your yeast the upper hand.

Awesome thread! One question though, has anyone worked through the two predominant methods ( using the isolating streaking from organic fruits v.s. Random beastie collections) in similar brews to compare tastes? Curious how the two co pare overall. They both seem to have worked here, is one better than the other?

BigPoppa502 said:

Awesome thread! One question though, has anyone worked through the two predominant methods ( using the isolating streaking from organic fruits v.s. Random beastie collections) in similar brews to compare tastes? Curious how the two co pare overall. They both seem to have worked here, is one better than the other?

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They both do work, no doubt about it. Is one better than the other one, that is hard to say. It depends on what you want to achieve.

If you collect anything that is floating around in the air, isolate colonies, streak, and brew with that, you will end up with what is around in the air at that moment you isolated your yeasts. It depends on where you are geographically, the temperature (time of the year), etc etc what you will get out of it.

If you for example take fruit with yeast on the skin, dump it in media, grow the organisms, isolate the yeast by streaking, you will end up with what was on the skin. These yeasts will be predominantly the species which thrive on the specific fruit, with maybe some contamination from the air.

I never tried the latter method, but did the first method twice. I ended up with two totally different results. One time I isolated two good old Saccharomyces cerevisiae, the other time I ended up with 6 Pichia fermentans strains. I performed the isolations at the same spot, but different times of the year. The beer resulting from the Pichia is not for the faint of heart, the beer from the Sacch. is much more approachable. This indicates that a single trial will give you very different results, and that you cannot really compare a single trial.

So, what is better? These two times indicate it can be hit or miss using method 1. Method 2 will undoubtedly result in beer, but which species you will isolate will depend on the fruit and how many colonies you isolate, what media you use etc.

So, what I am trying to say there is (arguably) not a _better_ method, but you will just have a different outcome, and you have to do it (at least?) ten times to get some statistical meaningful values.

I just sanitized a jar (shaking it for a minute while full of boiling water), sliced an unripe lemon (it was tough and green; I was impatient) and put it inside, then topped it off with 1.035 gravity wheat/pils wort left over from a Hefe batch. Put the lid on and stowed away.

I'm hoping to get wild yeast from the lemon skin and acidity from the lemon juice. Should this work? If it doesn't, I'll wait until the lemons get riper and try again.

Pith said:

I just sanitized a jar (shaking it for a minute while full of boiling water), sliced an unripe lemon (it was tough and green; I was impatient) and put it inside, then topped it off with 1.035 gravity wheat/pils wort left over from a Hefe batch. Put the lid on and stowed away.

I'm hoping to get wild yeast from the lemon skin and acidity from the lemon juice. Should this work? If it doesn't, I'll wait until the lemons get riper and try again.

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Where did you get the lemon from?

It's unlikely to work unless you picked it yourself. I'd suggest finding crab apples/other fruit or berry with a powdery substance on the skins where you can pick it. The problem is the northerners need to wait for that. It doesn't hurt to experiment but it probably was washed off long before it makes it to the store.

jaapie said:

Where did you get the lemon from?

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TheBreweryUnderground said:

It's unlikely to work unless you picked it yourself. I'd suggest finding crab apples/other fruit or berry with a powdery substance on the skins where you can pick it. The problem is the northerners need to wait for that. It doesn't hurt to experiment but it probably was washed off long before it makes it to the store.

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Yeah, I got it from the tree in our backyard. Should've clarified that, sorry. My "should this worK?" question was mainly in regards to ripe vs. unripe fruit, but it's moot now (see below). Also, the idea that the powdery substance on fruit is yeast is actually a myth in the vast majority of cases. That stuff is actually epicuticular wax bloom, a whitish haze caused by small crystals of wax, which occurs on the surface of many fruits. There is plenty of yeast on any fruit, whether or not it has that powder.

Anyway, it's been going great! I had been shaking the jar of wort plenty, so I guess the yeast were shaken off into the wort quite efficiently, because I took the lemon out a day or two later and there was a strong ferm happening after.

After the wort was nearly finished fermenting, I poured the liquid into a new boiled/cooled jar and discarded the hop/lemon sediment that had sunk to the bottom then whacked it in the fridge overnight. Discarded the liquid, poured some fresh wort into the jar with the yeast, shook it up and it's been going like that since.

Just a few hours ago I began the process of sorting out different groups of strains with similar flocculating abilities. The starter had been going a day or two and some yeast had already flocced to the bottom, so I tipped the fermenting wort into a new boiled/cooled jar, topped the flocced yeast jar up with water, shook it up and stuck it in the fridge, labelled "lemon starter, high floc".

I also did some using some unknown wild berries, but that's not as far along as the lemon one. I'll let you know if anything comes of it.

(PS: I'm from Australia. It's summer here, so lots of yeast!)

sorry...this threads been on for a while...and this has probably been asked. ...acetobacter....where does this fit in?? i

jaapie said:

They both do work, no doubt about it. Is one better than the other one, that is hard to say. It depends on what you want to achieve.....
So, what I am trying to say there is (arguably) not a _better_ method, but you will just have a different outcome, and you have to do it (at least?) ten times to get some statistical meaningful values.

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Thanks Jaapie. I think what you have laid out is reasonable enough. Still this is an interesting, exciting prospect. I will likely give this a go. Not sure I'm ready for it just yet being a n00b still.

I was curious how many of you have done this more than once from indigenous conditions, i.e. harvested yeast from the ambient environment outside your home.

I was hoping I'd capture my own house yeasts and then craft my beers around the house yeast, rather than the conventional manner of buying yeasts to match the beers one wants to make. I've done it a few times here in Tokyo, and to date, all my results have been pedestrian at best. I was dreaming of capturing a yeast that yields a strong, individualistic character of its own. So far, what I've captured has been remarkably neutral. No fruitiness. No strong esters or phenols. They all even flocculate well, demonstrate high attenuation, and ferment over a fairly wide temperature range. Just no taste. So, I guess I'm curious as to whether I should keep repeating this arduous process until I find something interesting, or should I just accept that the environment around my house just yields boring yeasts/microorganisms?

Hi Glossolalia,

First, I think its great that you pick up a yeast that ferments a beer very clean. We all dream of a yeast which will turn our wort into this fantastic Belgianesque wonderland of flavours (at least I do), but one should be happy when the beer is actually palatable after fermentation is done. Believe me, I have a ton of bottles sitting around which give a whole new dimension to the saying "in your face", and not in a really good way. I was totally unaware that these flavors existed before those yeasts made it happen.

You could brew maybe some nice beers in which the yeast plays a less pronounced role, or very subtle. You could give Scottish ale a Japanese twist, for example. But of course that is not what one thinks of when you say "wild yeast".

That being said - I find it very interesting that there is no noticeable difference in flavor (esters/phenols/etc) profile when you ferment at different temperatures. At what temperatures did you ferment your wort? Did you isolate your yeast, or are you using a consortium of organisms you picked up?

You could show the yeast who is boss by really stressing them, for example under-pitch, go so far as 35C fermentation (yes, I did this, and the beer came out nice for some, for others it was unbelievably bad), or under-oxygenate.

You say you isolated the yeast from Tokyo. That is a big city, and I guess you picked them from your garden? Was this at the same time of the year? How did you pick them up? With a glass of low gravity wort? There are some variables, and if you change them, I am sure you will pick up some different yeasts.

jaapie said:

That being said - I find it very interesting that there is no noticeable difference in flavor (esters/phenols/etc) profile when you ferment at different temperatures. At what temperatures did you ferment your wort? Did you isolate your yeast, or are you using a consortium of organisms you picked up?

You could show the yeast who is boss by really stressing them, for example under-pitch, go so far as 35C fermentation (yes, I did this, and the beer came out nice for some, for others it was unbelievably bad), or under-oxygenate.

You say you isolated the yeast from Tokyo. That is a big city, and I guess you picked them from your garden? Was this at the same time of the year? How did you pick them up? With a glass of low gravity wort? There are some variables, and if you change them, I am sure you will pick up some different yeasts.

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So, I've completed the process a total of four times. Twice in the late spring and twice in the early autumn. I'm pretty much putting out a glass jar of low-hopped, low gravity wort that I have slightly acidified with lemon juice and covered with netting to keep out insects. I'm putting the samples out on my patio, which isn't a garden per se, but I do have vegetables in containers there. I don't isolate individual yeasts via limited dilution or colony plating. So, it's likely a mixed culture. I do, however, feed them several batches of wort prior to using them in a beer. The beers I've made thus far have been mostly blondes with low hopping in an attempt to showcase the yeasts. The temperature ranges I used were more in the 18-26 C range. Maybe I'll try to go higher.

Sounds like you have picked up yeasts with very different profiles from batch to batch so perhaps I'll keep trying. So far, the yeast I've harvested from the dregs of my favorite Belgians have been far more interesting.

I'm going to have to try this today! I just so happen to have some light DME from making a starter and some agar agar from making vegan fondant (I'm not the vegan, don't worry.) I think I'll drive my truck into the Sierra Nevada foothills behind my house to the nice big hill with a lone conifer with a jar of medium and drink beer/read a book for a couple hours. I'll be sure to get some good stuff.

Tomorrow I will also be attempting to harvest pacman from a bottle of Rogue.... and I really want to harvest some yeast from the local juniper berries for our sahti (brewing liquor is boiled with juniper branches beforehand, berries go in at 5min boil addition.) Incorporating some fun yeast would make it all the better (either Myeast89506 or Myeast89507, whichever is more suited.) However I don't think the berries will be at their best... February seems to be the best time for sahti-approved berries.

SO EXCITED!

Glossolalia said:

So, I've completed the process a total of four times. Twice in the late spring and twice in the early autumn. I'm pretty much putting out a glass jar of low-hopped, low gravity wort that I have slightly acidified with lemon juice and covered with netting to keep out insects. I'm putting the samples out on my patio, which isn't a garden per se, but I do have vegetables in containers there. I don't isolate individual yeasts via limited dilution or colony plating. So, it's likely a mixed culture. I do, however, feed them several batches of wort prior to using them in a beer. The beers I've made thus far have been mostly blondes with low hopping in an attempt to showcase the yeasts. The temperature ranges I used were more in the 18-26 C range. Maybe I'll try to go higher.

Sounds like you have picked up yeasts with very different profiles from batch to batch so perhaps I'll keep trying. So far, the yeast I've harvested from the dregs of my favorite Belgians have been far more interesting.

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Sounds like what I did - only I did isolate the strains as well.

One reason for you getting the same outcome _might be_, is that you get a mixed culture, and you feed them several batches of wort prior to using them in beer.

Let's say that there is yeast "A" in there with a lot of other organisms. Yeast A ferments wort with a clean profile. Lets imagine Yeast A grows the fastest, and overtakes everything, and after feeding your consortium fresh easy to ferment wort for a few times, it is the major constituent in your wort, and you get a beer with a clean profile, resembling your previous beers.

Again, I am hypothesizing here, lots of hand-waving, I am not saying that this is what is happening, but it _might_ be. It would explain what is going on, a saying in biology is that you get what you screen for when you are looking for microorganisms. The fastest adapting organism will "win". It might also be, that you need to wait longer. The dynamics of a mixed culture of organisms fermenting your beer is very complex, some organisms are present dorment, and over-take the culture after a long time (months/year).

You could try to alter your selection mechanism, by altering parameters of your wort (how many times you add fresh wort, gravities, IBUs, oxygen content, FAN), or do something like change the temperature of your incubations. One suggestion is maybe to design a wort with a lot of harder to ferment carbohydrates, to make it a little less easy for the clean yeast you have in there.

Another option, which might give a better outcome, is to isolate the organisms somewhere else. A lot of those spontaneous fermenting brewers in Belgium are not sitting in the country side, but are situated in more city-like settings. I read somewhere that you actually get better results in the city when you want to isolate sour yeasts (Brettanomyces/Dekkera), but I cannot find the reference. I do not know if this also counts for other strains. Either way, it is not so exciting to have a house yeast from somewhere else, but it might be just the thing you need.

HTH,

J

PS what are you favourite Belgians?

So I've tried this multiple times and would always just get mold. Being in Texas it's not that big of a shock. But a few nights ago the weather report said the mold was very low and it was quite cold (mid 40's). So I threw together some DME at about 1.020 and put it outside for just the night. Brought them in and covered them. Well last night I noticed a few c02 bubbles rising to the surface. Huzzah! I have wild yeast. Smells like pineapples and funk, so there's probably some Brett. Going to step it up and brew a saison with it soon.

I apologize if this has already been brought up:

I left my DME/agar medium outside for a few hours yesterday... a little breezy, so that probably helped. Right now it's incubating in my window (~80*F)

When should I expect to see cultures?

If you have anything at that temperature I would say 3-4 days at the most. Most of mine were clear and strong in only 2-3. I let mine form a clear colony before I streaked it tho.

I love the thread and would really like to capture my own yeast, but I'm a little overwhelmed by the 60+ pages and have a few questions. My original plan was to just follow the instructions in the original post and leave a mason jar of wort sitting on my windowsill for two weeks and, assuming I see some bubbles on it and there's no mold, pitch it into a fresh batch of wort. Going by some other posts, it sounds like I should boil the wort that I'll be leaving out with some hops first to keep the mold at bay. Should I put some cheesecloth over it? There's seems to be some disagreement as to whether or not that's a good idea. After the two weeks, should I make a starter from the yeast I've captured? My understanding is that wild yeast is pretty aggressive and a starter shouldn't be necessary. Finally, should I use separate equipment when brewing with wild yeast? Going by the original post, there shouldn't be any bacteria in the mason jar after the two weeks so I'm not sure it'd be necessary. Thanks!

Yeah, boil and hop the wort, and leave it out with cheese cloth. Time seems to really depend. Took me 2 weeks to get anything but just takes a couple of days for others.

Glossolalia said:

I was curious how many of you have done this more than once from indigenous conditions, i.e. harvested yeast from the ambient environment outside your home.

I was hoping I'd capture my own house yeasts and then craft my beers around the house yeast, rather than the conventional manner of buying yeasts to match the beers one wants to make. I've done it a few times here in Tokyo, and to date, all my results have been pedestrian at best. I was dreaming of capturing a yeast that yields a strong, individualistic character of its own. So far, what I've captured has been remarkably neutral. No fruitiness. No strong esters or phenols. They all even flocculate well, demonstrate high attenuation, and ferment over a fairly wide temperature range. Just no taste. So, I guess I'm curious as to whether I should keep repeating this arduous process until I find something interesting, or should I just accept that the environment around my house just yields boring yeasts/microorganisms?

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Sorry but I find this rather funny; even the yeasts in Japan are clean and efficient.

epbx said:

Should I put some cheesecloth over it?

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I never use a cheesecloth, but judging from the success of others who use it, there may be enough yeast suspended in the air to sufficiently inoculate a wort.

But if you can attract a sugar-loving insect, you've got an even higher chance of catching a nice Saccharomyces strain. The wild habitat of beer yeast is, after all, the sap leaking from wounded trees. Unless you are lucky enough to find a tree with slime flux, the quickest way to get this yeast into your wort is transfer by insect.

Some have claimed that the cheesecloth prevents acetic acid bacterial contamination. It's a little hard to believe that these bacteria are not found wherever yeast is found. So if yeast are in the air, you'd expect vinegar producers to also be in the air. Their niche is an alcohol and oxygen rich medium, so you expect them to come along for the ride wherever yeast fluorishes. Brewers have always limited their growth by preventing oxygen exposure, which is what we have to do as wild yeast wranglers. It's the oxygen, not the cheesecloth, that causes vinegar-producers to grow.

Why don't you try both, and you can do the experiment I've always been too lazy to try!

OK, so I went with the cheesecloth. I'll let you all know how it goes. I'm sure I'll have a few more questions, too.

epbx said:

OK, so I went with the cheesecloth. I'll let you all know how it goes. I'm sure I'll have a few more questions, too.

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I used a cheesecloth as well. Worked for me. Yeasts are also airborne, so it should be ok.

I'm having a similar problem as Glossolalia had. The wild yeast I've captured seem to have a fairly boring everything. They do all the things his Japanese strains do. The ones isolated from the berries are particularly neutral; the lemon one has some strange, not-entirely-pleasant-or-unpleasant aromas and a sliiightly unpleasant taste, that would probably be easily masked by a more complex brew than a 1.036 DME wort.

Just keep searching, I guess! Theoretically there are different colonies of yeasts on different fruits, since the ones that like each fruit are going to be different, so I guess I'll keep looking until I find one that asserts itself. Maybe I'll wander down to the gully tomorrow if my tailbone recovers sufficiently...

Pith said:

. . . . Just keep searching, I guess! Theoretically there are different colonies of yeasts on different fruits, since the ones that like each fruit are going to be different, so I guess I'll keep looking until I find one that asserts itself. Maybe I'll wander down to the gully tomorrow if my tailbone recovers sufficiently...

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You can keep searching, there are going to be numerous different yeast strains in any wild sample however, so you may be getting the result of one faster yeast or you may be getting the result from numerous yeasts working together. You may try fermenting at different temperatures to get the influence from different yeasts. For instance if you ferment at a lager temperature for a few generations you may be able to isolate a good lager yeast, argueably if you ferment for a few generations at a saisaon temperature you may get a good saison yeast.

Possibly if you limit the sample where you are getting the yeast, like say use one single cherry in a sealed fermentor with some boiled and hopped wort and step it up from there, you may get less strains of yeast than if you used a bunch of cherries, etc. Then again, maybe not.

I was under the impression that most yeasts from fruits were extremely numerous or at least that was supported by my extremely unscientific tests with muscadines but I only did two seasons worth.

Pith said:

The wild yeast I've captured seem to have a fairly boring everything

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Keep in mind that it took brewers generations to produce the boringness of Chico ale yeast. You could have caught a clean-fermenting wild strain. But the chances that a neutral-character domesticated yeast from your brewery slipped in are high. Did you do any controls in which you repeat everything except inoculation to determine how likely contamination is?

COLObrewer said:

You can keep searching, there are going to be numerous different yeast strains in any wild sample however, so you may be getting the result of one faster yeast or you may be getting the result from numerous yeasts working together. You may try fermenting at different temperatures to get the influence from different yeasts. For instance if you ferment at a lager temperature for a few generations you may be able to isolate a good lager yeast, argueably if you ferment for a few generations at a saisaon temperature you may get a good saison yeast.

Possibly if you limit the sample where you are getting the yeast, like say use one single cherry in a sealed fermentor with some boiled and hopped wort and step it up from there, you may get less strains of yeast than if you used a bunch of cherries, etc. Then again, maybe not.

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drummstikk said:

Keep in mind that it took brewers generations to produce the boringness of Chico ale yeast. You could have caught a clean-fermenting wild strain. But the chances that a neutral-character domesticated yeast from your brewery slipped in are high. Did you do any controls in which you repeat everything except inoculation to determine how likely contamination is?

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I got one sample of yeast from a lemon off our tree, and another sample off a small bunch of wild unknown berries. There are no breweries around my area except for Sun Masamune Sake Brewery which is at least 10km away.

Also it's summer here in Australia so I imagine the yeast I found would be happy to ferment at warm temperatures, rather than cool temperatures. Unfortunately I don't have the means to do different temperature experiments except as the season changes.

I don't mind getting neutral character. Free yeast is free yeast. I'm basically just trying not to get unpleasant flavours.

And there's no doubt I have multiple strains in each batch. I separated the lemon and berry starters into different levels of flocculation (ie poured wort into a separate jar when something flocculated, then washed the flocculation and let the rest of the wort ferment, repeat process when more yeast flocculates) but obviously it's a sloppy system and I'm still getting lots of strains. Until I can get my hands on some proper lab equipment, it will have to be slap-dash "bucket biochemistry" for me.

Pith said:

There are no breweries around my area except for Sun Masamune Sake Brewery

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In your brewery, your home, have you ever brewed with a neutral-character yeast like Chico? Most homebreweries are covered in it. That seems like a more likely source of contaminating domesticated yeast. It's pretty easy to know if you're catching it or not. Just set up one or two collecting vessels in parallel to your catching vessel. Do everything to them that you do to your experiment, except don't open the controls for inoculation. If no yeast grows in the controls, then you know the rest of the yeast you caught is actually wild, or at least feral.