Per Wyeast’s recommendation, now doing a D-Rest with the 2124 and the Diamond.
The beer was very near FG when the temp was raised from 50 to 66F.
So, how long should the rest be…2 days, 3, 4? It is still bubbling away.
A one ounce sample was taken, and it tasted perfectly fine.
The answer is yes. It’s as long as it needs to be. If you don’t taste d, it’s done.
I agree. Diacetyl doesn’t always happen, so the rest is not always needed. If you’re not smelling or tasting butter, you can safely skip it or just do a short rest.
On the other hand, in my experience, when I get diacetyl, I find it doesn’t just take a few days to disappear, but closer to 3 WEEKS. Nothing a little patience can’t cure. No one else says this but based on the same thing happening to me many dozens of times, you can’t convince me I’m wrong. ;D
You’re right for you. You’re wrong for me.
In my last beer that showed diacetyl, it was not evident as it was being transferred to the serving keg. We thought it tasted fine.
Later on, after clearing and carbonation, it reared it’s ugly head.
It might have been there from the start, but we did not notice it at 32F.
I understand that can come from O2 exposure.
Just did a German pils with Diamond Lager at 52f. D rest for 2 days at 56f. Sample at 56f showed no signs of diacetyl but did a forced D test and got lots of butter, so not crashing yet. Will test again in a few days.
I saw that also. In our case, the beer was gravity fed very quietly into a stainless keg that had been completely purged of oxygen, using CO2. It is not likely that oxygen was the culprit. Especially after such a short time.
Acetolactic is oxidized to diacetyl.
From George Fix:
“I have seen cases in which wort constituents (melanoidins and tannins), oxidized on the hot side in wort production, were passed on to the final beer, only to play the role of oxidizer there.”
All beer has Diacetyl. It may be below the human perception threshold, but it is there.
I have had beers that were fine then get dinged in competition due to O2 exposure when going from the keg to bottle.
Did another forced diacetyl test 2 days later and it was all cleared up. So, the answer in this particular case… How long? 4 days.
Just started slowly dropping the temp for the crash. Total D-Rest time has been 4 days now. Did not detect any diacetyl or other off-flavors in the beer. Hope this one turns out good, I have high hopes for it.
I find this as well. I don’t get diacetyl often, but when I do it takes its sweet time to clear. Of course I’m kind of “set it and forget it” when it comes to fermentation, and don’t generally discover diacetyl until I’ve transferred to a keg which is when I first taste the beer. It eventually clears, but the timeline for me is a couple of weeks rather than days, even if I leave it at room temp rather than in the kegerator.
Did a diacetyl rest with my last beer, a Pale Czech Pils. Tasted the beers while near the FG at 50 degrees, and did not pick up any off flavors. But did not want to take a chance, so let the temp go up to 66F for a week. Then crashed, and kegged the beer earlier today.
The beer tastes very good so far. With a little aging and carbonation, it should be a hit with my friends and neighbors. Giving away lot’s of beer lately! Just gave a friend 5 gallons of 5D. Gave the same guy 5 gallons of Schwarzbier a week ago.
That’s what happens when you brew faster than you can drink. I actually like brewing more than drinking.