So I did a wort stability test on a batch I made back in September. I immediately smacked myself in the head because I used a mason jar (and lid) that previously had yeast in it and knew I didn’t wash it well enough. Shockingly, it had a krausen on it a day later. I tossed it in the fridge after it looked like it was done fermented and figured I’d deal with it later.
Well I checked it today and it has a pretty nice sour smell to it. Pictures are below… but what do I do with it? Taste it and see? Keep it? I’ve just started getting into sours and I’d love to have a “house bug”, but I’d like to hear from someone with more experience than me on this.
Any idea if the beer is fully fermented? If it had been left at ambient temps, I would think it would be safe by now if the pH is below 4.5. IIRC, the mad fermentationist said after 3 months a wild fermented beer should be safe. Googling his site, I didn’t see where he said that but you might be interested in this article: American Lambic - Spontaneous Fermentation | The Mad Fermentationist - Homebrewing Blog.
If it tastes OK (spit don’t swallow), consider adding fresh wort so you have a 1/2 gallon to 1 gallon of this stuff. Let it ferment at room temp for several months. In the meantime confirm if what I remember about when it is safe to drink these things is correct.
Give it a taste and see if you like it. If you do then toss the contents into a larger batch.
You said it had yeast in it beforehand. Was this yeast you bought? If so then you might have some of whatever was in the mason jar before in this mix. If it’s sour or funky then you at least have some other stuff with it.
Pretty sure it’s fully fermented, and I’m gonna give it a taste test later today. If it’s good, I’ll do as you suggested and add it to a 1 gallon of starter wort and let it sit for a while.
So I tasted it. Slight souring, but with a high fusel alcohol component and some slight funkiness. I pitched it into a 3L starter and am gonna let it ride for a while.
