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Diacetyl rest

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enohcs

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Im making a 1.061 lager that reached 1.024 yesterday. It has been fermenting for two weeks at 53f. I'm raising the temp for a DA rest, not that I detect any DA, but I don't think I can get the temp up to 65 where I was aiming. My garage is hovering around 61. I'm assuming that resting at 61 until fermentation completes will be fine, but I thought I would check.
If I did detect DA, would the lower rest temp be an issue?
 

dale1038

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Imo, its too late for a diacetyl rest. You should move the beer the minute you see the krausen begin to fall. Moving the beer now, should help you drop a couple points in gravity though.
 

Begin2Brew

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My last few lagers I fermented at 52 for 5 days then just set the fermentor on my basement floor. The thermometer read anywhere from 62 to 66. I just left them there for three weeks and then rack a lager. Doing this I have never tasted diacetyl in any of the finished beers. I think at 61 you'll be fine.
 

jetmac

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From a post by Denny Conn:

Once you remove the beer from the yeast, you can't simply warm it up to remove diacetyl. Diacetyl reduction isn't done by the temp per se...you warm the beer to make the yeast more active to consume the diacetyl. I've had kuck reducing diacetyl by krausening...adding actively fermenting wort to the finished beer. But it's kinda a PITA so be sure you have diacetyl in there in the first place and that it's bad enough to hassle with this.

I would say, bring it inside, if you still have active yeast in it, they should warm up and consume the diacetyl
 

dale1038

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From a post by Denny Conn:

Once you remove the beer from the yeast, you can't simply warm it up to remove diacetyl. Diacetyl reduction isn't done by the temp per se...you warm the beer to make the yeast more active to consume the diacetyl. I've had kuck reducing diacetyl by krausening...adding actively fermenting wort to the finished beer. But it's kinda a PITA so be sure you have diacetyl in there in the first place and that it's bad enough to hassle with this.

I would say, bring it inside, if you still have active yeast in it, they should warm up and consume the diacetyl
Which is kind of what I'm saying. If you let the yeast fall out before you warm the beer it really won't help much. Fwiw I make a lot of lagers and dont mess with rests at all anymore. I've never had an issue with diacetyl.
 

jetmac

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Which is kind of what I'm saying. If you let the yeast fall out before you warm the beer it really won't help much. Fwiw I make a lot of lagers and dont mess with rests at all anymore. I've never had an issue with diacetyl.
They're not dead. Warm them up and they'll think it's time to go back to work. Not converting sugars but cleaning up the shiat left behind.
 

dale1038

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I didn't say dead. I said fall out of suspension. In my experience once they fall out its never quite the same getting the yeast to finish out. Will they wake up and try to clean? Sure. Will it be an optimum diacetyl rest with the best possible fermentation? In my opinion no. All this being said, I've made good beer both ways.
 

osagedr

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1.024 in most cases is not too late to do a d-rest, but given your OG of 1.061 it's pretty borderline. It depends on the yeast strain. The way to know for sure when to start your d-rest is through a forced ferment test so you know what FG will be.

For every person who says they've never done a d-rest and never had a problem there is at least one person who says they never used to do d-rests until they had their first d-bomb. Personally I find them easy and costless to do, with zero downside. Lots of brewers only do them when they deem them necessary, i.e. if they taste diacetyl in their lager before fermentation is complete.
 
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enohcs

enohcs

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dale1038 said:
Imo, its too late for a diacetyl rest. You should move the beer the minute you see the krausen begin to fall. Moving the beer now, should help you drop a couple points in gravity though.
Unfortunately I can't see the krausen since I'm using a stainless conical. I'm going on gravity. Usually you do the rest when fermentation is 75% complete. All the yeast is still in place, I haven't dumped yet. Fermentation had slowed, and raising the temp has shown a lot more activity in the airlock which is one reason I'm not too concerned.
 

makomachine

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Bottom line - do the rest at 61 and you'll be fine. There is much argument on the when or if it's necessary, but believe there is a consensus that it won't hurt your beer.
 

jetmac

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Unfortunately I can't see the krausen since I'm using a stainless conical. I'm going on gravity. Usually you do the rest when fermentation is 75% complete. All the yeast is still in place, I haven't dumped yet. Fermentation had slowed, and raising the temp has shown a lot more activity in the airlock which is one reason I'm not too concerned.
That's a good sign. How have you gone about raising the temperature? It prolly needs to be about 10F higher than your fermentation temp.
 
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enohcs

enohcs

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jetmac said:
That's a good sign. How have you gone about raising the temperature? It prolly needs to be about 10F higher than your fermentation temp.
I have a Johnson controlled fridge that I kept at 54. Then I raised the temp on the controller to 65, but obviously since the garage is only at 61, it's not going to get any higher than that.
 

jetmac

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I have a Johnson controlled fridge that I kept at 54. Then I raised the temp on the controller to 65, but obviously since the garage is only at 61, it's not going to get any higher than that.
Put a lamp in the fridge or a heating pad(i use to use this)
 
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enohcs

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So here's an update and new question.
My lager started at 1.061 and took 14 days to get to 1.024 (fermention slowed way down as it reached 1.024).
I raised temp to 64 (due to temp in my garage it took 4 days for beer to reach 64). Fermentation rate increased for the first couple days. It went from 1.024 to 1.018 in 3 days. Now it's day 6 at the DA rest temp and gravity is 1.016. I'm trying to get it down to 1.013 - 1.014.
Should I let it hang out for 3 or 4 more days at 64, or should I proceede to lager?

I'm using a conical and I haven't dumped any yeast yet. Should I do a dump? Will that re excite the yeast to finish out?
 

osagedr

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1.061 is a big beer; it's probably done. Nothing will be harmed by leaving it on the cake for a few more days as planned. Dumping your trub won't help you ferment anymore, but it's time to dump and move to lagering anyway. You can cool the beer slowly (3-5 degrees per day) if you wish or just crash it. Lots of folks feel safer with the former option.
 
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enohcs

enohcs

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osagedr said:
1.061 is a big beer; it's probably done. Nothing will be harmed by leaving it on the cake for a few more days as planned. Dumping your trub won't help you ferment anymore, but it's time to dump and move to lagering anyway. You can cool the beer slowly (3-5 degrees per day) if you wish or just crash it. Lots of folks feel safer with the former option.
I'm using WLP820. Says that it's max attenuation is 73%. 1.061 to 1.016 is 73%. I guess it's done.
 
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