Diacetyl rest
Moderator: slothrob
Diacetyl rest
I have heard of doing a diacetyl rest from different readings for the yeast. My question is, what exactly is a dacetyl rest and how should it be done?
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- Posts: 8
- Joined: Wed Jan 12, 2000 4:55 pm
Good question
I wouldn't mind knowing the answer to that too. Diacetyl is that butterscotch flavor right?
The real truth...
A diacetyl rest is done towards the end of fermentation to help speed up the tired yeast metabolism so that it can reabsorb diacetyl.
Traditionally this is done in Lagers where diacetyl is a big flavor flaw. Diacetyl will build up to a higher level in a cold fermenting beer
because colder liquids can absorb more and because there is less CO2 scrubbing out the diacetyl during subdued fermentations. The key
is to start the fermentation cold and then let the temp rise towards the end, in the case of an ale, raise the temp of a fermenting lager to
60
Traditionally this is done in Lagers where diacetyl is a big flavor flaw. Diacetyl will build up to a higher level in a cold fermenting beer
because colder liquids can absorb more and because there is less CO2 scrubbing out the diacetyl during subdued fermentations. The key
is to start the fermentation cold and then let the temp rise towards the end, in the case of an ale, raise the temp of a fermenting lager to
60
Just before lagering?
Just to make sure I've understood in the lager case:
Ferment at (say) 50 degrees for a week
Raise to 60 for 2 days
Then finally down to 1-2 degrees and lager for 3 weeks or whatever.
That right?
Ferment at (say) 50 degrees for a week
Raise to 60 for 2 days
Then finally down to 1-2 degrees and lager for 3 weeks or whatever.
That right?