How to remove this Diacetyl?

[Shoemaker]

Had an octoberfest fermenting at 55 degrees. Brought the temp up to room temp near the end of fermentation for a diacetyl test. I've just tasted the beer after 4 days and I taste butter.

Should I leave the beer on the yeast cake at room temp for the taste to clear up or lager it? Is there any chance this taste will go away?

 

[Yooper]

Had an octoberfest fermenting at 55 degrees. Brought the temp up to room temp near the end of fermentation for a diacetyl test. I've just tasted the beer after 4 days and I taste butter.

Should I leave the beer on the yeast cake at room temp for the taste to clear up or lager it? Is there any chance this taste will go away?

Yes, leave it on the yeast cake at room temperature until the diacetyl is gone- it will NOT improve with lagering and may worsen.

If it's not getting better in a day or two longer, you could try gently swirling your fermenter to encourage the yeast to keep working.

 

[boo boo]

What Yooper said.

Lets get into the cause of it while we are talking about reducing it.
Did you start your fermentation warmer than recommended? Sometimes a warm start
to fermentation will make more diacetyl than can be changed after fermentation has finished.
That is only one of a few causes of diacetyl in excess of normal, that can be prevented.
Hopefully it will work out that it will be changed with further contact with the yeast and time.

 

[markg388]

Please post results! When I was in your position a few months ago i did the room temp swirl thing for only 2-3 days and the diacetyl persisted, and I impatiently dumped the batch. I've been undecided ever since if that was the right move or not, I didn't even need the bucket or anything, it was one of dumps that happens during a fit of rage. Yooper is definitely right that lagering won't help, been down that road too.

PS - 55 IMO is too high for a lager, you'll get better results at 50. Good luck!

 

[Revvy]

Here is the UBER thread on Diacetyl. Preventing Diacetyl -or- "Hold The Butter Please"

 

[ArcaneXor]

I am personally familiar with two cases were the diacetyl was reduced to acetoin with fruity notes during extended cold storage. More likely than not it was actually the agitation of the yeast during racking than the actual lagering that caused this, however. So I'd suggest warming the batch up and getting the yeast back into suspension; maybe even feeding it a little bit to get it back to being active. If it really is diacetyl, that should take care of it.

 

[Shoemaker]

Yes, leave it on the yeast cake at room temperature until the diacetyl is gone- it will NOT improve with lagering and may worsen.

If it's not getting better in a day or two longer, you could try gently swirling your fermenter to encourage the yeast to keep working.

So I swirled the yeast, waited a few days and I don't taste any improvement. In fact, it tastes worse.

Now, I made a 10 gallon batch and my other 5 gallons of this batch actually tastes great....no diacetyl. I'm about to lager it.

Would it be a good idea to take some of the slurry from the good batch and put it in the diacetyl tasting one? Perhaps this will get the yeast going again?

 

[markg388]

i say do it, what else do you have to lose?

 

[Bensiff]

I would toss the slurry into a starter and get it to high krausen then toss it when it is most actively breaking down diacetyl to maximize reduction