Wild Yeast Fermentation

[Deebo]

So I was a bit bored and collected a bunch of wort and trub in a 2l soft drink bottle and thought I'd sit it outside to see if something would ferment it.
Today it has a nice froth on the top and actually smells pretty good.. is there anything I should know about before taking a swig in a few days to see how it tastes.
It was 31c here today so I am suprised it doesnt have an awful smell to it really (it is sitting in a shady spot).

 

[ekul]

You should know about skunking. The UV light can make your hops turn into skunk goodness. BUt you'll smell it before you'll taste it anyway. Maybe put the bottle in a dark place now that its innoculated.

 

[Deebo]

You should know about skunking. The UV light can make your hops turn into skunk goodness. BUt you'll smell it before you'll taste it anyway. Maybe put the bottle in a dark place now that its innoculated.

Thanks for the tip, have just stuck it in a dark room.

 

[CONNOR BREWARE]

Thanks for the tip, have just stuck it in a dark room.

was there anything in particular near like fruit trees,keep us updated

 

[Deebo]

was there anything in particular near like fruit trees,keep us updated

Nah no fruit close to where I put it.. I was actually a bit suprised that stuff got down the small neck of the soft drink bottle in such a short time.

Heres a pic, stirred up the trub a bit moving it into the light.

 

[pk.sax]

+1 very interested. Been trying wild with cider of juice, be great to know what it does to beer.

Maybe you can blend half pints of wild beer with normal and tell us if that's any good too?!

 

[Swinging Beef]

You are a brave man.
All my experiments with natural airborn yeasts in Australia have proved to be quite revolting.
We do not live in Lombeek.

 

[mckenry]

is there anything I should know about before taking a swig in a few days to see how it tastes.

Probably that youre going to need somewhere to spit it out really quickly. :lol:

Interested to hear about it though. I've never had a 'natural yeast' / spontaneous fermentation taste good.

 

[Deebo]

Probably that youre going to need somewhere to spit it out really quickly. :lol:

Interested to hear about it though. I've never had a 'natural yeast' / spontaneous fermentation taste good.

I wasnt expecting more than a pile of mould really, but had another sniff today and it smells like beer fermenting normally smells to me.
It has got a lot more murky now that the fermentation is moving the trub I had in there all around. (it is kinda of mesmerising watching it move around, will upload a video if I can remember)
I do have another smaller bottle of wort in the fridge without any trub I may try to innoculate with the yeast from this one if it doesnt turn into a horrible sour mouldy mess.

 

[CONNOR BREWARE]

Loving this thread

If you knew this was not gonna be rank that size bottle could make a good starter for the experiment on a bigger scale. Still you'd have to be a braver man than to risk that much wort.

 

[esssee]

Check out the October 20, 2011 episode of Basic Brewing Radio link. They spoke about Spontaneous Fermentation. Interesting Stuff.

 

[super_simian]

I've had spontaneous fermentation occur (due to a brain fart) to a small batch of wort ~500ml. The smell wasn't particularly off, so I let it go (in another part of the house from my brewing gear - I'm a suspicious man!) After 2 weeks I had a bit of a look/smell/taste. It had thrown a kind of slimy 'krausen', smelled very 'phenolic' and hadn't attenuated much. The taste was mainly sweetness, with a bit of a baked-bean aftertaste. Not awful, but not great.

 

[drsmurto]

Not necesarily bad. A lot of wine is made using wild yeast.

Wild ferments normarily result in large ester formation.

If i was doing this i would be treating it like normal beer so fit an airlock or somehting to protect it from any further 'contamination'. You could always add some SO2 to inhibit baterial growth (lacto/aceto) at 30mg/L using potassium metabisulphite. It wont stop the yeast from fermenting at that level.

You are likely to see the gravity end up much lower than with beer yeast so you might be best to either stop fermentation (rack/crash chill) at your desired FG to retain some body.

Another person interested in seeing how this pans out. :icon_cheers:

I have mates who make wine naturally at a professional level who are interested in doing the same with beer.

 

[Josh]

I've done it a couple of times. Pretty pleased with the results. Though after 7 months, the Framboise is pretty subdued if you were looking for overly funky flavours. But it finished at 1.003 from 1.036 I think. Makes a very tasty, ridiculously sessionable beer. At least that's the experience I have in my backyard. Everyone will be different.

 

[Deebo]

Looks like fermentation has stopped today (has been pretty warm in perth the last few days so may effect the flavour somewhat).
I will take a sg reading and have a taste on the weekend and if it isnt horrible will maybe try collecting some of the yeast and fermenting something else in a cooler spot.
I have a porter waiting to go in a cube so I could draw some of that off for the wild yeast and ferment the rest as normal, or just try another small sample using about 750ml of wort I have in the fridge (I think a lighter beer would give a better idea what flavours the yeast are putting out).


Edit: Couldnt resist so had a small swig.. It tastes slightly sweet (probably a bit under attenuated) and has a very slight bitter taste but overall is pretty drinkable. I reckon once chilled and carbed could pass for an ok beer. Considering it had temperature going against it I am already thinking I may risk an old fermenter and a batch of beer to give it a shot when I get a chance.

In the mean time is the best way to store it just chuck it in the fridge? I think I will try drawing off 750ml into a PET bottle and using a carbonator cap to give it some fizz after I do the SG reading.

 

[drsmurto]

Whats the SG?

If it has finished fermenting then i would be crash chilling it for a few days to drop out as much yeast as possible and then pour into another bottle and use the carbonator cap.

Sounds like you are onto something.

I like the idea of a wild ferment but not something funky.

 

[argon]

I'm really keen to try this too. Like the idea of a few wild ferments from trying to select the most preferable strain.

Something like set-out half a dozen bottles around the place. Let them inoculate/ferment out and select the best tasting one. Then use that to inoculate the next small batch in a controlled environment. Over time (probably a long time) be able to select the house strain.

Also one thing to consider... the bottle may have been inoculated by a strain of yeast you've been using to brew with in the past and it's somehow got into the bottle. So it may not be a wild yeast at all. Not that it makes the experiment any less fun though. :icon_cheers:

 

[hsb]

I was reading Wheeler/Protz on Lambics/Sours/spontaneous fermentation last night (as you do)

Interesting stuff to a complete noob at wild fermentation like myself. They pointed out some stuff that is probably obvious to others but wasn't to me. Essentially pointing out that, unless you live next door to an orchard or a cereal crop, there's probably nothing unique about your local environment, the wild yeasts/microorganisms are just everywhere, if not already in your wort - it's about setting the right conditions to encourage growth from the ones you want (and suppressing the ones you don't.)

I can scan it if anyone's interested, though like I say probably common knowledge to many of you - and the focus was more on lambics/sours etc..

 

[Greg.L]

A wild ferment is unlikely to be a single strain of yeast. Part of the flavour is from a progression of different yeast strains. If you save the yeast residue from your ferment it will probably taste different next time. The point with wild ferments is you have to start from scratch each time.

 

[Deebo]

Haven't done a SG reading yet hopefully will do one tommorow then chill it down.

The fact it wasnt weird/sour etc made me think it may be a brewing yeast but I have only ever pitched yeast inside (the bottle was left outside).
I do ferment in a fridge out there, but the yeast would have to get out of the airlock and out the fridge door and traveled about 3 meters then into the bottle.

Only other way I can think that brewing yeast got in is that I do pour my trub down the drain.. but it would have to have hung around the drain for about 2 weesk then got out up into the air and into the bottle.
I also usualy pour starsan and napisan down the drain after it so not sure how well it would survive in there.