Stuck fermentation?

[Finn]

Hi guys! So three days ago I racked my Bohumbug Pilsner off its lees, topped it up with boiled/cooled water and set it out in the woodshed to lager. It was not fully attenuated when I racked it -- I wanted to give it a short diacetyl rest, but it tasted so good I decided not to mess with it -- but since I've racked it, it's shown no evidence of activity whatsoever. Should I be worried? I figured it would at least generate enough fermentation activity to push a bubble through every six minutes, but ... nothing.

It's been averaging 35 degrees in there.

Thanks!

--Finn

 

[DAAB]

What was the OG, FG and the yeast you used?

 

[Yooper]

At 35 degrees, it's too cold to ferment. That's lagering (storing) temperature, not fermentation temperature. If it's not finished fermenting, you shouldn't rack or lager.

Keep it at 50 degrees or so (whatever temperature your yeast likes) until it's done, then start the lagering process. And like DAAB said, the og, current sg, and the yeast you're using will help us give better advice.

 

[malkore]

and racking off the large yeast cake is only going to hinder finishing the fermentation.

i've actually caused a stuck mead by racking too early, and then had a hell of a time coaxing it back into fermentation due to the alcohol levels that had been created prior to racking.

 

[Finn]

Uh-oh. So my OG was 1.066 and I brought it down to 1.040 in primary, so I'm pretty sure it's nowhere near full attenuation. I racked it after two and a half weeks in primary. Guess I better drag it on into the lager shack, get it back up to 45 degrees and hope for the best. It's yeasted with WLP830 (German Lager).

If I do have a stuck fermentation, would you recommend drawing off some krausen from the dopplebock to kick-start it? That one's using a WLP Bock yeast, I don't remember the number.

Or, I suppose, I could go buy me another vial of 830.

On the bright side, if I ferment it a bit more and rack again, I can go buy me a Corny keg to put it up in, and then I don't have to worry about a thing 'til Spring.

I'm expecting I should be able to get the ferm unstuck OK because it's still so low in alcohol. But, this is my first lager, so who knows?

Thanks guys!

--Finn

 

[Yooper]

At 1.040, it definitely isn't done. It should taste very sweet at this point. You may have a little trouble getting it going again but definitely bring it to 50 degrees and try.

Next time, remember to not rack your beer until it's done fermenting, and then you can lager.

 

[DAAB]

I'd be tempted to get a 1L starter going with a fresh yeast (or even from yeast skimmed from the DB you mentioned) to make sure you are pitching suffient yeast. Ideally it should be fully active as pitching it into beer isn't the friendliest enviroment for a yeast.

You should always check the gravity before deciding whether to rack, the arbitary 1-2-3 rule is completely pointless.