Name That Infection (see picture)

[knash3]

Oatmeal stout in primary for 3 weeks, gunk on surface I've never seen before. Yeast was healthy, 2 L starter went great, pitched on temperature, no issues I was aware of until opening to check FG (1.14). Is it infected?

 

[parjay]

That's infected, looks cool though!

 

[Homergah]

Yes that's infected, unless you were going for a natural mixed fermentation. If so, perfect! The structure on top is biofilm and is known as a pellicle. It can be lacto, pedio, and/or Brett. Might be good, if you like that kind of thing. One thing is for sure, you probably should get a new bucket and any hose that has touched that beer.

 

[Home_alone1]

Add some Brett to it and let it age ! If it’s Pedio the Brett should clean up the dms the pedio makes ! Sour stout !

 

[RPh_Guy]

Facts:
A lot of different microbes form pellicles.
There's no way to know what contaminating microbe(s) are in your beer just by looking or tasting.
It's not dangerous.

Next steps:
If it tastes and smells fine, go ahead and package it.
Keep a close eye on the carbonation level if you bottle. Over-carbonation is possible.
Clean your cold-side equipment well. Or if you're the paranoid type, dedicate it to sour beers or throw it away.

In my opinion adding more microbes to it now is a bad idea.

 

[day_trippr]

Awesome! Book it!

 

[knash3]

Thanks guys, I did taste it and it had no real funk to it. I'll get more serious about evaluating and either kegging or dumping it next. This is only the 2nd bad batch in 5 years, so I guess my number was up.

 

[IslandLizard]

Sour Stouts can be really good, even accidental ones! Don't dump it unless it's absolutely putrit.

That fermenter will need a good scrub, disassembly, close inspection, and likely a bleach bath.

 

[AkTom]

Garrett. Name it Garrett.