Howto: Capture Wild Yeast

Hi Mindghost,
Fishing out the mold colonies may have only gotten rid of the mold fruiting bodies. Fungal growth is often invisible, and it is occurring long before we see the colored reproductive structures. Not sure about the tan colonies -- are they attached to the bottom of the glass?

Hey guys, almost every attempt on this forum to capture wild yeast has resulted in catching mold and bacteria. Even if you do have some wild yeast mixed in, it will be unusable unless you get rid of the mold.

The best way to capture wild yeast is not to just leave wort out in the air. As you all have found, this captures just about everything! You want to be selective:

The best way to do this is to get your hands on some agar and some sterile dishes. Take some wort and make a 2% (that means 2 grams in 100 mL) agar solution. Boil the wort-agar and pour enough into each plate that it just covers the bottom.

After the plates cool, take a ripe or overripe fruit directly from a tree and rub it on the agar surface. Don't touch the part of the fruit you're rubbing or the agar. Close up the plate and grow for several days. If you just open it in your home, or near a window, you're going to catch the stuff that already lives in your home -- bread mold! We all eat bread, and we all sometimes keep it until it's moldy. Our houses are bread mold factories! Go outside! Go to a fruit tree! Get your wild yeasts there.

If you get a dense lawn of growth, take a sterile loop and streak the growth onto another plate. Eventually you should pick single colonies that are opaque and creamy. Grow them up in 10 mL of sterile wort for several days and then pour off a little bit to taste. Pick the tastiest!

The next best method is instead of streaking out on agar for a pure culture, simply discourage the growth of spoilage organisms in your collection. Remove some highly-hopped beer from your fermenter when it's only partly attenuated, say 25%. Boil it to kill yeast, but remove from the heat as soon as it boils. You don't want to boil off the alcohol.

Leave this pasteurized 25% attenuated wort uncovered near wild fruit trees or bushes. The hops and alcohol will discourage the growth of bacteria and mold, but wild yeasts will do just fine. The alcohol will also attract fruit flies, which is great! They carry loads of wild yeast on their bodies, which they pick up from every ripe fruit they visit.

No more mold! This thread is starting to look like fungal pornography.

Thanks,

I just got home and checked the apple juice. Again, several small colonies of mold on the surface, but at the bottom it is coated with that same stuff I mentioned in a previous post. The apple juice smells like beer (ie - "yeasty") so I believe that I was able to catch wild yeast, and that is what's growing at the bottom. So cool, even if I can't use it for anything

I just put a mason jar out on my patio to try and capture some wild yeasties.

After capturing several samples I have one that is looking way better than the others. Although I think I gagged when I noticed my batch of chili was also fermenting. Not mold, FERMENTING. OMG.

Chili ??????

I am beginning my first attempt at capturing some wild friends today. I'll make updates on the process...

I left mine outside, and After one week, I think I've caught mold. I'll have to check it in the morning.

electric_beer said:

After capturing several samples I have one that is looking way better than the others. Although I think I gagged when I noticed my batch of chili was also fermenting. Not mold, FERMENTING. OMG.

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I've had batches of green salsa start to ferment on me before. In some things it can be nice, lots of really traditional foods have fermented counterparts, to help storage life previous to refrigeration.

Three days in and I definitely have a bacterial infection. A thin -- and growing -- white pellicle is forming over the top and it's starting to develop some small white bubbles.

Fortunately, no mold yet.

Freezeblade said:

I've had batches of green salsa start to ferment on me before. In some things it can be nice, lots of really traditional foods have fermented counterparts, to help storage life previous to refrigeration.

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Yeah, seeing chilli BUBBLE actively was pretty nasty. However the successful capture seems too be looking good. Just gotta hope I don't get any mold!

I finally caught yeast. It showed about 5 days after the mold did.

I'm heading out now to find some Agar and do the petri dish thing. I'll probably put it out Monday.

Edit: I didn't realize I was going to have to drive all over hell to find it. First health store: none. Second health store: doesn't exist anymore. Found it at the third, down the baking isle.

After putting out some apple juice which caught a few things (see my previous posts), I decided to just try to get some fermentation going for the heck of it. I figure that the worst thing that could happen was that I'd waste a little honey (I do mead, not beer), water, and yeast nutrient but I might get to see something cool grow in the jar. Over the course of a week or so, all visible signs of mold disappeared and I was left with crystal clear liquid which has a strong alcohol smell, and 1/8 inch of lees at the bottom. Kinda cool.

So last night I took a bigger jug (3 pound plastic jug the Shop Rite honey came in), put a simple must together (all tools sanitized), dumped most of the clear fermented liquid out (being careful not to lose the lees), and dumped most of the lees into the jug. Added some raisins, yeast energizer, and yeast nutrient. This morning it is bubbling away. SO COOL

I took some of the lees and put it in a test tube with some sanitized spring water and stuck it in the fridge. As to the must now fermenting, I'm going to let it go for a few days, then move up to a 1 gallon batch if there is no visible sign of infection. Even if there is and the batch is unusable, this has been a fun experiment.

mindghost said:

After putting out some apple juice which caught a few things (see my previous posts), I decided to just try to get some fermentation going for the heck of it. I figure that the worst thing that could happen was that I'd waste a little honey (I do mead, not beer), water, and yeast nutrient but I might get to see something cool grow in the jar. Over the course of a week or so, all visible signs of mold disappeared and I was left with crystal clear liquid which has a strong alcohol smell, and 1/8 inch of lees at the bottom. Kinda cool.

So last night I took a bigger jug (3 pound plastic jug the Shop Rite honey came in), put a simple must together (all tools sanitized), dumped most of the clear fermented liquid out (being careful not to lose the lees), and dumped most of the lees into the jug. Added some raisins, yeast energizer, and yeast nutrient. This morning it is bubbling away. SO COOL

I took some of the lees and put it in a test tube with some sanitized spring water and stuck it in the fridge. As to the must now fermenting, I'm going to let it go for a few days, then move up to a 1 gallon batch if there is no visible sign of infection. Even if there is and the batch is unusable, this has been a fun experiment.

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Could we see a pic or two?

ReverseApacheMaster said:

Could we see a pic or two?

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Sorry for the delay. Here's a photobucket gallery of the fermentation in the honey jug, and today I moved it to a 1 gal. I used a different honey for the full gal than was used to start the fermentation... I hope that's not a problem but we'll see.

In the pics you'll see a lot of chunky white stuff on the surface. That's bees wax (the honey I used for the starter was in a jar with a honey comb and several loose pieces).

Some of the pics are blurry. My camera wigged a bit in trying to shoot that close *shrug*.

http://s32.photobucket.com/albums/d32/mindghost/Wild Mead/

Saccharomyces said:

I just had success cultivating wild yeast from an organic apple using only apple juice. I don't know if it is suitable for beer, but after three generations the sample I just tasted tasted slightly lactic but very tasty. We will see how it goes. I am planning to build this yeast up for another 3-4 generations and then pitch it into a batch of cider.

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I have just had a similar success!




On Friday I sanitized a quart mason jar and filled it about halfway with apple juice, and tossed in some fresh red and black raspberries that grow on our property, and covered it with cheesecloth fastened with multiple rubber bands. For most of the day yesterday, the jar was sitting in the shade underneath an apple tree. At the end of the day I could see some bubbles clung to the berries. Overnight it sat on the window sill with the window open, and this morning is bubbling away slowly but steadily.

Now for the questions, how do you "clean up" the yeast? I was going to slowly add juice to the jar until mostly full to keep the yeasties fed, then pitch into a gallon of apple juice and let 'er rip.

When it is ready to be pitched into a gallon of juice, do I just add the liquid, the berries, the sediment(if any), or do I just swirl it and dump it all in?

Many thanks for your help!

Eric

emr454 said:

I have just had a similar success!




On Friday I sanitized a quart mason jar and filled it about halfway with apple juice, and tossed in some fresh red and black raspberries that grow on our property, and covered it with cheesecloth fastened with multiple rubber bands. For most of the day yesterday, the jar was sitting in the shade underneath an apple tree. At the end of the day I could see some bubbles clung to the berries. Overnight it sat on the window sill with the window open, and this morning is bubbling away slowly but steadily.

Now for the questions, how do you "clean up" the yeast? I was going to slowly add juice to the jar until mostly full to keep the yeasties fed, then pitch into a gallon of apple juice and let 'er rip.

When it is ready to be pitched into a gallon of juice, do I just add the liquid, the berries, the sediment(if any), or do I just swirl it and dump it all in?

Many thanks for your help!

Eric

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Very cool!

I'm by no means an expert... just a guy fumbling his way through something I'm finding fun, but I can tell you what I did (this is to make a mead):

1 - Once I suspected yeast growth, I added some honey, water, and yeast nutrient
2 - Once that cleared and all visible activity was gone, to move my catch from the mason jar to a size up I dumped out most of the clear liquid and dumped the sediment into a must. Added some yeast energizer, nutrient, and some raisins. It started bubbling within a few hours
3 - After 3 days of bubbling away I mixed 1/2 gal of must and dumped the whole starter into it through a sanitized strainer (to catch any raisins, and bee's wax). Filled up with spring water. That was yesterday at about 4:30 PM
4 - Within a few hours I had tremendous foaming, and this morning the airlock is going nuts! I'm getting a bubble every 1-2 seconds, though most of the foam is gone. Wild yeast are beasts!

I've got updated pics, and a 45 second video in my photobucket account here:

http://s32.photobucket.com/albums/d32/mindghost/Wild Mead/

Good luck!

Another question, when I step this up from 1/2 qt. to 1 qt. or so, would it be beneficial to use a stir plate? My first batch with this is going to be a gallon, or maybe I'll use a 4L Carlo Rossi jug. Anyway, I should only need to step this up to about a quart for a gallon/4L cider batch, right?

Oh, should I airlock this at anytime?

Sorry for all the questions, I'm just getting a little excited that its working out like it should!

Eric

mindghost said:

Wild yeast are beasts!

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Yeah, those suckers'ill eat anything =O

I just put out my second wild yeast trap. I used a ratio of 1 tablespoon agar and 1 tablespoon dme to 1/2 a pint of water. I'll give it 4 hours capture time.

Just an update on the status of my spontaneous fermentation. In an earlier post, I had a quart jar about half full and once it began to show steady fermentation, I stepped up to about 1L.



As before, I added some more fresh picked, unwashed red and black raspberries to the apple juice when I stepped it up. That was on Monday. Now, on Wednesday, it is showing an even more vigorous ferment, and surprisingly enough, it looks as though the black raspberries lost their color and the red berries are still, well, red! Oh yea, so far no mold or sign of infection!

I can see more yeast residue on the bottom of the jar, and that is giving me hope! I think when I add this starter to my cider, I'll decant about 3/4 of the juice(and drink it, of course!), swirl the remainder and add that to the juice in the carboy.

I may try my hand at yeast washing whenever my cider is done. I'm just going to do 1 gallon for now as a trial. If that yields good results, then the next step is 5 or 6 gallons!

Eric

Not even 3 days and the agar solution is showing signs of growth. I think I have some mold and some yeast.

I think my first test for it will be to culture enough for my hearth bread recipe and check it's flavor. After that, maybe a mini extract beer or a mini mead. Actually, that might be the perfect time for making wassail.

Mmmm wild wassail.

Keep in mind that each time you change the environment, your wild-caught yeast undergo a selection event. For example, you wouldn't want to use your yeast to make bread, then propagate those same yeast into a beer.

Instead, take part of your wild-caught culture and just use it for bread -- take another part and just use it for beer.

That was the plan. I just wanted to check and see if I could detect any sour or other flavors from it in the bread.

Besides, I don't think you can extract live yeast after baking at 425F for 30 minutes.

My wild yeast mead is bubbling along. Smells quite sour, which is kinda cool. Mead is not typically "sour" so I'm interested to see how the overall flavor turns out

Update: On Friday, I took my stepped-up "starter" of wild yeast, apple juice and berries, decanted 3/4 of the liquid, swirled and poured the remainder into 1 gallon of apple juice. I added 3/4tsp of both Fermaid-K and DAP per hightest's nutrient addition schedule. By the next morning, fermentation is very vigorous. There is a constant barrage of bubbles rising to the surface of the liquid and the airlock is virtually boiling! I cant imagine it will take long to ferment out the gallon of juice at this rate.

Specifics:
The juice I've been using had an Original Gravity of 1.052. It was plain, Wal-mart, "no sugar added" apple juice. I used this since I began this experiment, but have added some fresh-picked berries to it. I don't know how much sugar, if any, the handful of berries contributed to the juice, so I am going to consider it negligible. Who knows what the final gravity is going to be?

When I decanted the larger of the two starters I made, I poured some into my hydrometer test jar to take a quick gravity reading. It was 1.020 on Friday. This larger starter had been fermenting since Monday morning.

Taste: I drank the hydrometer sample along with the rest of the liquid that was decanted. My wife said it smelled a little bit like vinegar, but not very strongly. I could smell it and taste it as well, but it was very faint. It could be from the fresh picked berries having a little acetobacter on them, since I threw them in right from the plants. I know I didn't get any fruit flies in the starters. Is it possible it is just the nature of the wild yeast that was utilized? I don't know. I do know I absolutely abhor the taste and smell of vinegar, so it was just barely noticeable to me, or else I wouldn't have drank it.

Another thing is, I didn't use a stir plate on the starters, I just shook the starter every once in a while. Could the oxygenation have caused a slight acetic taste? I'll leave that to more experienced brewers.

In conclusion, it fermented well, hasn't gotten infected as far as I can tell, and tasted decent for something completely unpredictable as wild yeast.

I will let this 1 gal batch ferment to completion, bottle it, wash the yeast, and then decide, once it has carbonated, if it is worth replicating.

Good luck fellow brewers!

Eric

I've read through most of this thread, I was wondering if anyone knows where/how one would capture lager yeast? Is it just a random thing? Would you have to capture it somewhere when it is very cold? I've captured some yeast https://www.homebrewtalk.com/f163/can-i-culture-yeast-juniper-berries-169156/ but I am pretty certain it is ale yeast. More testing forthcoming. If I use this same yeast in a lager environment (~40F-55F) could it possibly naturally select some lager strain(s) within the yeast? Or would I have to start it in that temperature?

Keep on yeasting my friends

I've thought about this a bit. My reasoning is that it's easier to isolate a lager monoculture than an ale monoculture.

My reasoning is set out your jar when you have 45F to 55F temps outside so the lager yeasts are more likely to be active in the air. Then grow them in your jar at 45F to 55F. The ale yeast will grow substantially slower than the lager yeast. So what you harvest out of the jar will be the lager yeast.

It might take several culturings along those lines to ensure you only have lager yeast.

Btw, why I posted: had to move my agar jar outside. It's got too much funk to stay in the house.

Beernik said:

. . . . . it's easier to isolate a lager monoculture than an ale monoculture. . . . .

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Why? would not the reverse be true if you collected at ale temp's and cultivated at ale temp's?

Keep on yeasting my friends

Lager yeast works at ale temps. It just doesn't taste right.

Beernik said:

Lager yeast works at ale temps. It just doesn't taste right.

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I see, so the yeast I cultivated from the juniper berries could be lager yeast? What will it taste like if so? Diacetyl?

Unless you've put forth effort to isolate one or the other, I'd assume you have both ale and lager plus potentially other species of yeast.

The parts that are lager yeast would give you some steam beer qualities (if you have it). And funk would come from the stuff that's not ale or lager yeast.

I'm wondering if ale yeast can be isolated by skimming the top of an active fermentation.

Beernik said:

Unless you've put forth effort to isolate one or the other, I'd assume you have both ale and lager plus potentially other species of yeast.

The parts that are lager yeast would give you some steam beer qualities (if you have it). And funk would come from the stuff that's not ale or lager yeast.

I'm wondering if ale yeast can be isolated by skimming the top of an active fermentation.

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Good call, will have to keep that in mind during testing, maybe skimming from multiple generations would isolate it completely.

My wild cider is still bubbling away, albeit a bit slower than before. It is only a gallon and I am wondering how long it will take to finish, these wild yeasts seem to be slower than others, but I am guessing that is normal. It is still cloudy as all get out. It will be very interesting to see the end result. I'll keep posting on its progress as it develops.

Eric

Here is the latest news on my wild cider attempt.

https://www.homebrewtalk.com/f127/possible-brett-my-wild-cider-what-temp-ferment-187770/

I am both excited and a bit disappointed. I am excited because I've caught yeast and not mold, but it looks like Brett and may take a few months before I can taste it and see if this experiment was worth all the time involved.

I so want to take a sample, but don't want to damage the pellicle.

Eric

Hi Emr,
Pellicles are formed by any aerobic microbe grown in a static liquid culture. They form when microbes cooperate to form a sticky buoyant layer in order to support themselves at the air/liquid interface. They can only grow there because they need the oxygen in the air. (Even if you're using an airlock, there's still a small amount of oxygen in the headspace.)

What you have could be any alcohol-tolerant aerobic yeast or bacteria. No reason to think it's Brett yet. If you can get your hands on some antibiotics, you can make up an antibiotic wort that will kill bacteria but spare yeast. 50 micrograms per mL of chloramphenicol is standard for isolating wild yeast from bacteria. Also, you can drop the pH of the wort to 3 or 4 using .7% 1 Molar hydrochloric acid. If you can't get your hands on either HCl or Chloramphenicol, a 5-10% lemon juice wort might get you in a bacteria-killing pH range.

Don't worry about disturbing the pellicle. You may plunge some of the pellicle into the anaerobic depths of your fermentation, but you'll open up new real estate at the air-liquid interface, and you'll probably get new growth there.

Good luck!

Dear COLO and Beernik,
Lager yeast is a hybrid between two naturally-occuring yeasts, Saccharomyces cerevisiae and Saccharomyces bayanus. All lager yeasts looked at so far are highly-related to each other, while ale yeasts have much greater genetic diversity. So though we can't rule out a natural origin of lager yeast, it is probably man-made.

You probably won't isolate the same yeast hybrid from nature, but you might be able to select for some cold-fermenting yeast. You could try cold-fermenting wort inoculated from a natural source, or you could try starting warm and decreasing the temperature a few degrees each time you dilute your culture into fresh wort. Try both! You might be able to create your own lager yeast.

Keep in mind also a few other things: Fritz Maytag's steam beer yeast was created by starting with a lager yeast, then fermenting it warm until it acquired the ability to grow at ale temperatures. It was not some sort of natural lager yeast used at higher temps.

Also, it is impossible to be sure you have a pure culture unless you grow on solid media. Even if you skim from several generations of a liquid medium, you will still probably have a mixed culture. Actually, you wouldn't even know if it were mixed or not unless you grow on solid media or look in a scope. Invest in a pressure cooker, some agar, some sterile plates, and an alcohol burner. You're at the stage of yeast wrangling where this equipment is essential.

Sorry if this message is a repeat. I had a posting FAIL with my previous message...
Good luck!

drummstikk said:

Hi Emr,
Pellicles are formed by any aerobic microbe grown in a static liquid culture. They form when microbes cooperate to form a sticky buoyant layer in order to support themselves at the air/liquid interface. They can only grow there because they need the oxygen in the air. (Even if you're using an airlock, there's still a small amount of oxygen in the headspace.)

What you have could be any alcohol-tolerant aerobic yeast or bacteria. No reason to think it's Brett yet. If you can get your hands on some antibiotics, you can make up an antibiotic wort that will kill bacteria but spare yeast. 50 micrograms per mL of chloramphenicol is standard for isolating wild yeast from bacteria. Also, you can drop the pH of the wort to 3 or 4 using .7% 1 Molar hydrochloric acid. If you can't get your hands on either HCl or Chloramphenicol, a 5-10% lemon juice wort might get you in a bacteria-killing pH range.

Don't worry about disturbing the pellicle. You may plunge some of the pellicle into the anaerobic depths of your fermentation, but you'll open up new real estate at the air-liquid interface, and you'll probably get new growth there.

Good luck!

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Lager yeast is a hybrid between two naturally-occuring yeasts, Saccharomyces cerevisiae and Saccharomyces bayanus. All lager yeasts looked at so far are highly-related to each other, while ale yeasts have much greater genetic diversity. So though we can't rule out a natural origin of lager yeast, it is probably man-made.

You probably won't isolate the same yeast hybrid from nature, but you might be able to select for some cold-fermenting yeast. You could try cold-fermenting wort inoculated from a natural source, or you could try starting warm and decreasing the temperature a few degrees each time you dilute your culture into fresh wort. Try both! You might be able to create your own lager yeast.

Keep in mind also a few other things: Fritz Maytag's steam beer yeast was created by starting with a lager yeast, then fermenting it warm until it acquired the ability to grow at ale temperatures. It was not some sort of natural lager yeast used at higher temps.

Also, it is impossible to be sure you have a pure culture unless you grow on solid media. Even if you skim from several generations of a liquid medium, you will still probably have a mixed culture. Actually, you wouldn't even know if it were mixed or not unless you grow on solid media or look in a scope. Invest in a pressure cooker, some agar, some sterile plates, and an alcohol burner. You're at the stage of yeast wrangling where this equipment is essential.

Sorry if this message is a repeat. I had a posting FAIL with my previous message...
Good luck!

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I like you

Welcome to HBT.

Very intersting stuff there drummstikk, I had suspected the juniper yeast to be a mixture of yeasties since it has yet to fail in fermenting anything I throw at it. In the future I will be testing it in a lager and also saison to see what it does, I did save some from the original starter in a tube. I will probably need to build from that for these extreme cold and hot tests.

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.

drummstikk said:

. . . . . .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.

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Yes, it does sound like a lot of work, Me being me, I,ll probably just use it and abuse it until it stops working then go get some more.