The other day I transferred a Russian Imperial Stout into a bourbon barrel. In the process I siphoned some beer into a pint class to sip and take a gravity reading. After letting it sit out for a day or two a thick layer of white mold has formed. I’m concerned that not only is my batch infected but that I just infected my barrel! Anyone experience this?
A have a photo but I’m not sure how to upload it here so heres a link:
Should I dump?
It looks like a pellicle which is not mold thankfully. It might have been introduced in the glass. The is one way to find out, pull a bit out of the barrel and taste it. If it is infected than yes, the barrel is infected too and you can start your sour beer project now.[emoji1]
What was the gravity reading? could it be krausen? Doesnt look like mold, not hairy enough.
Shouldn’t be krausen since I brewed it 3 months ago - gravity is 1.009 which came down from 1.020 a couple months ago when I transferred to a secondary so it’s possible somethings eating at it.
Hmm, glass is possible - it didn’t really taste sour. If it doesn’t seem like a health risk I may keep it rolling and move a batch of cider in next.
Seems unlikely that a pellicle would form in that short of a time.
I would not worry about your batch. Looks like something in the glass or airborne.
I would imagine a commercial brew left in a glass would look the same after 2-3 days.
only takes a couple days…check this starter…3-4 days max…(bottom post)
https://www.homebrewersassociation.org/forum/index.php?topic=5579.0
You’re probably right - I just let a sample in another glass sit out for some days and there is no sign of anything.
1.009 seems like an awfully low FG for an imperial stout, makes me think infection.
What was your OG? I agree that 1.009 sounds low for a RIS.