Lager Diacetyl Rest

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MikeDelta1

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I have been fermenting a pils and a Oktoberfest at around 52 degrees (may have gotten up to 58 for a day, that souther german lager yeast fermented like a beast in the Oktoberfest, the Budvar in the pils seemed a little less explosive). I checked the gravity late Thursday night and was at 1.020 for the pils (SG 1.049) and the Oktoberfest was at 1.018 (SG 1.065) so I set my controller to 65 for the rest took about a day to get there. So now what do I do should I check the gravity again to make sure it fermented out or start dropping to 34 degrees for the lagering? I'm assuming I want to drop the temp slow like two or three degrees a day which would give it time to ferment out. Should I transfer over to the keg to lager now or after I reach 34. If you can't tell this is my first lagers and I've done a lot of reading but there are a lot of contradictions out there. I just droped the temp to 63 just now so I figured I have about 10 days to make a decision either way.
 
I've done a lot of reading but there are a lot of contradictions out there.

That is the truth and you are going to get a sampling of that again. What I did when I first lagered was to pick a method and try it, take good notes, taste tests and adjust your method as needed.
 
Yeah, I'd give it a couple days at 65F. Certainly won't hurt the beers. Then check the gravity. If you're sure the yeast is finished, I'd crash it to 34 right away, not ramp down. The only reason to ramp is to keep the yeast in suspension and working, and not crash them to the bottom. If they're done, I don't see a need to keep them working. If you pitched cold and pitched enough, you should have a great, clean lager already.
 
I've done 3 lagers so far and here's what I did:

Fermented at 48 until krausen dropped and fermentation slowed.
Moved carboy out of keezer and let it come to room temp (68F) and left it for 7-10 days.
Transfered to keg, put back in keezer and dropped the temp to 33F for 4-6 weeks.

The first was an Irish Red and it was lagered in a rum barrel. It has been bottled and needs to age - the oak is a little strong, but otherwise it was delightful.

The second was a Prima Pils clone and it was so good I drank it all before I could bottle any. :drunk:

The third was an Oktoberfest (went on the Pils yeast cake) and I'm not going to touch it until September.
 
I've done a lot of lagers over the years and I second what Run has done. I let mine ferment at about 50 or so until about 80% done, then allow to warm up to room temp for a few days, then rack, then cool down slowly to lagering temp. You can certainly allow to rest for longer at room temp, but from my experience, 3-4 days is enough. I have never tasted diacetyl. Lager as long as you can; you won't be disappointed if you let it sit for longer than you think it needs.
 
I've done a lot of lagers over the years and I second what Run has done. I let mine ferment at about 50 or so until about 80% done, then allow to warm up to room temp for a few days, then rack, then cool down slowly to lagering temp. You can certainly allow to rest for longer at room temp, but from my experience, 3-4 days is enough. I have never tasted diacetyl. Lager as long as you can; you won't be disappointed if you let it sit for longer than you think it needs.

That's how I do it too!
 
Thanks for the input, somtimes validation that I'm on the right track helps with the relax don't worry part. I'm stepping down 3 degrees twice a day and when i get to the low 50's I'll take another gravity reading before taking it all the way down.
 
Not all lager yeasts require a diacetyl rest. I use wyeast 2206 and 2000. I typically ferment at 50F for a minimum of 3 weeks but preferably 4 weeks. I then keg and lager for a month if I can wait that long. One big advantage of a diacetyl rest (other than removing diacetyl) is that you can turn over the fermentation faster. 10 days at 50F, then 2-3 days at 60F, and then lager. I like the way my lagers taste with a 3-4 week fermentation at 50F. That said, if I were running a business, I would not tie up fermenters for 4 weeks. One advantage of home brewing - dollar signs don't get in the way.
 
I think part of my problem is that I'm not sure what diacetyl tastes like. The sample I took seemed a little sweet if anything. I used the Wyeast Budvar yeast on the Pils and I hope it dries out a bunch because the hops are very much in the background. The Oktoberfest used White Labs Southern German and it is still sweet also and a little fruity but the temp did get up on it probably no higher than 58 before I caught it and forced it down to the low 50s, the fermentation went off like a rocket so we'll see. Even with a little fruity taste the Oktoberfest won't be bad.
 
I think part of my problem is that I'm not sure what diacetyl tastes like. The sample I took seemed a little sweet if anything. I used the Wyeast Budvar yeast on the Pils and I hope it dries out a bunch because the hops are very much in the background. The Oktoberfest used White Labs Southern German and it is still sweet also and a little fruity but the temp did get up on it probably no higher than 58 before I caught it and forced it down to the low 50s, the fermentation went off like a rocket so we'll see. Even with a little fruity taste the Oktoberfest won't be bad.

If you're not at FG (stable SG at least three days in a row), don't start dropping the temperature!

What happens in my lagers: ferment at 50 for about 10 days until SG of 1.020 or so. Raise to diacetyl rest. Once fermentation is over, as confirmed by hydrometer, the beer is racked to a carboy. Then the lagering is begun.

Diacetyl in small amounts as an "oily" or slick feeling on the tongue. That's what you're looking for. If you detect any hint of a slick mouthfeel, the diacetyl rest isn't over!

Before racking, ensure that there is no hint of diacetyl, and that the FG is reached. Then, racking and lagering can begin.
 
What happens in my lagers: ferment at 50 for about 10 days until SG of 1.020 or so. Raise to diacetyl rest. Once fermentation is over, as confirmed by hydrometer, the beer is racked to a carboy. Then the lagering is begun.

After racking, do you ramp down the temp., or take it down quickly?
 
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