Spontaneous fermentation

[Matplat]

So as many of you probably do, I collect all remaining wort including trub in a separate container after filling the cube/FV, then when trub settles out, use the cleared wort for starters.
I have had a bottle of such wort sitting for a few weeks now waiting to be used, and the other day I noticed a krausen at the top of the bottle. I thought I had sealed it reasonably well at 90+ degrees, but I guess only so much can be expected from a normal plastic bottle lid.
Is there a chance I can extract a unique yeast strain from it once its done? Or is it likely to be a combo of bugs that will only cause problems? I figure this is how people first started fermenting beer way back when....?

 

[Yob]

You might get lucky.. Never know till you have a go

 

[MHB]

Yes there is a chance, there is also a chance you will win lotto, 1 in several million.

If we take a realistic look at the possibilities: -
Being a brewer there is going to be a lot more yeast in your environment so it might be one of them.
It might be a wild yeast, of the millions of yeasts a couple of thousand make good beer, you do the odds.
Who says its a yeast, there are more bacteria on earth than all other lifeforms added together, a fair fraction of them think wort is yum.

You can ferment it out, taste it and if it is good go ahead and propagate it, just be aware that by far the most likely reason for it tasting good is that it is a yeast you brought at some time.

Yes you are right, at some time this is how yeast were selected, but there were a hell of a lot of tippers during the process.
Mark

 

[Matplat]

Yep, I figured as much.... fortunately my garage has been pretty consistent around the 20deg mark for the past few weeks so if it doesn't taste good, it shouldn't be from over temps....