spontaneous fermentation

The other night I got a wild hair and started brewing at about 10 at night, a golden ale. Since this wasn't a planed brew but a spontaneous one I didn't start my starter till the same time. After I finished brewing l transfered to my sanitized carboy and put in my fermentation chamber untilled my starter would be ready three days later "today". So today I went to pitch my start but the beer appears to be fermenting " bubbling air lock, and foam ring ." So I didn't pitch my yeast Coz I want to see what happens. My question is if this turns out to be a spontaneous fermentation is their anything I should do to help it? Or just any other random input.

Unfortunately it's probably some form of bacterial/fungal infection.

When you sanitize your equipment it's not the same as sterilization. No matter what you do at home, you will always have some form of bacteria/unwanted fungi living on your equipment.

Sanitation in brewing is all about giving your yeast enough of a head start that they consume all the sugars and crowd out any bacteria before they can grow to troublesome numbers.

Unfortunately by leaving your sugary wort for 3 days you let whatever was living there grow/reproduce enough that you have visible fermentation.

There's and off chance that the fermentation is being caused by yeast cells from the last time you used that carboy but it's more likely something else.

IMO pitch your yeast and hope for the best, they might still be able to take the lead and crowd out anything problematic.

That leads me to anouther question that I didn't ask original but didn't want to lead to confusion what visaul difference are their between a spontaneous fermentation compared to an infection and will they both drop my gravity

It's absolutely infected but not necessarily ruined, but until very recently this was the way beer was made. You will probably end up with a sour but hey, it might be great.

Cultured yeast might be able to get in there and take over, depends on their competition factor but I don't think any beer yeast are killers, only wine yeast.

Might have gotten semi lucky and caught some wild yeast instead of an infection. Check it in two weeks to see where the gravity is as well as the flavor.

Draken said:

Might have gotten semi lucky and caught some wild yeast instead of an infection. Check it in two weeks to see where the gravity is as well as the flavor.

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Thats what I was thinking. The fact that he has krausen is hopeful. Infections dont make Krausen. Yeast does. I'd pitch and hope for the best.

Now we're two vs two for infected vs a wild yeast fermentation. I would like to see it by yeast for obvious reason and like to see it ferm out this way to see what I get with out pitching the 1056 any one have a definite reason why it would be one over the other

IMHO if it is yeast it's not wild, but probably cells leftover from the last time you used the carboy XD

ForsythBrewery said:

Now we're two vs two for infected vs a wild yeast fermentation. I would like to see it by yeast for obvious reason and like to see it ferm out this way to see what I get with out pitching the 1056 any one have a definite reason why it would be one over the other

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Pitch your yeast. Wild yeasts can still lead to off sour, cidery flavors. You are prolly brewing a sour beer right now. Why two of us think there is a chance it could be wild yeast is you have a foamy head of krausen on top of the beer. Most bacteria that are drawn to beer typically dont do this.

Personally I can't imagine why you'd want to let it run its course, it seems to me you'll have 5 gallons of vinegar or something worse... I'd say pitch your yeast now.

Also, three days is way too long for a starter, 18-24 hours is all you should do, see this video from Greg at Wyeast:

Maybe you did only brew your starter for a day and then two days in the fridge to get the yeast to drop so you could decant the starter liquid off, i don't know...

Lots of off information here. Some bacteria will form krausen. Especially lactobacillus which is an extremely common bacteria. It's on you, in you and on pretty much anything warm. It's probably that you have both bacteria and wild yeast in your beer. It's not like it has to be one or the other. Both can even ferment at the same time.

There's no guarantee the flavors of the wild yeast will be enjoyable. There's no guarantee the flavors of the bacteria will be enjoyable. So obviously, no guarantee you will enjoy any combination. I've had some yeast-driven infections that were just nasty as all get out. I've had some bacteria-driven infections that were pretty good for about a year before they started to turn nasty. I've collected wild stuff off fruit that produced some really interesting flavors over time. Sometimes really gross, then later really interesting, then back to gross, then even better. Wild fermentations are just different creatures.

If you are willing to give up the fermenter for a year or so then let it ride. If you're not, see where it goes in a month or two and either bottle or dump.