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Diacetyl Rest Question

Hi all. Quick question (or two). My NB Czech pilsner has reached the two week mark. Before i secondary, should I give it a diacetyl rest? Is this necessary for this style?

Also, should I just set it out at basement temps (60 degrees’ish) for a few days, secondary, then place in the fridge (40 degrees)?

I LOVE your fermentation cave.

You should tell us what yeast strain you used to get good advice on whether a d-rest is necessary or not. But I’d say I don’t think doing one could ever hurt!
If you do one you’ll want to raise the temperature ten degrees (or more) above the fermentation temperature, hold for a few days or until fermentation is complete, and then transfer to secondary and lager at fridge temps.

Thank you for the advice. My hole in the wall, at least in the winter, stays at about 50 degrees. My basement, if I close the heat vent, stays in the low 60’s. So it sounds like this should work okay. I used Wyeast 2278.

That is an awesome fermentation chamber.

Thank you. It was there when my wife and I bought our house. Not really sure what the original purpose was (wood shoot?), but one of the previous owners worked at a company in town that makes walk-in coolers. Looks like he sourced the material for the hatch from his workplace, lol.

I was actually about to post a thread about this very topic as I’ve got the same beer going at the moment and I’m just about ready to a d-rest myself. Cheers.

Yep, same beer/yeast fermenting in my spare bedroom as well. Wyeast website doesn’t mention doing a d-rest like their 2124 (which I used for my Bohemian Pils a few months ago), but I always like to do a d-rest for a week moved to the kitchen then keg. Kitchen temp around 65F.

I believe a smart fellow on this forum named Sean Terrill that if you pitch enough healthy yeast you shouldnt need a d rest. But if you want to, just do it. Its not hard to do and its a short portion of the process anyway.

It depends on how much diacetyl you like in your Bohemian Pilsners. How big was your starter? What’s the gravity?
2 schools of thought on when or if to do a diacetyl rest. After 2/3 of the fermentation is done (by measuring the gravity) raise the temperature 10 degrees or so for 2-3 days. Then transfer off the yeast and into a secondary and gradually (I do 5degF/day) lower the temperature down to 30-32F. Or just leave it at 50 degF after reaching your final gravity for a little longer.

Take a gravity sample to see where you are in fermentation. Then taste it. If you taste diacetyl, do a rest. If you don’t, then don’t.

That looks like a handy little psuedo cave. No other comment for you on the D-Rest, but I have a comment that you might want to take into consideration.
Next time you do this, you want might to put something over the concrete. Keeping a glass carboy on that rough concrete could be harmful. Take it in and out could cause chips on the bottom of the carboy, leading to a huge mess and possible injury.

I agree completely. I used my PET carboy, with a few old six pack carriers underneath it. i’m thinking of putting a plastic cutting board in there or something like that.

Yeah, that looks like PET in the picture. I agree, glass in there could be trouble and when those things break (which they do!), they bust into a million pieces. Anyway, I make a lot of lagers and I d-rest every single one just as an insurance policy. I regularly use 2124, 2278, 830, 2308, 2001, 940, etc. I take it out of the fridge and rest it on the basement floor for 2-3 days, then go to secondary where it goes back into the fridge. Nice cave! Cheers.

Thank you! And I just wanted to say thanks again for all the info. This is my first lager (should have realized the hole would serve that purpose long ago), and so far, looks good and smells great.

If that is a recent picture and you still have 1 or 2 inches of kraeusen and are still in active fermentation and should wait longer. It is important to let lagers sit on the yeast to clean up.
Most of my lagers are not ready to do a D-rest till about 4 to 5 weeks. But each one can be different. Anyway I always do one and wait till the kraeusen has started to fall back into the beer to do it.

That was about two weeks ago…or thereabouts. The kreausen has fallen. It’s getting the fridge treatment today. And then i play the waiting game…

This seems long. Are they very high gravity lagers? Leaving a lager in primary for that long is not a problem at all but 4-5 weeks seems agonizingly long to me. Mine are usually 2-3 weeks-ish.

Ken, I don’t know why but my Lagers seem to take longer to ferment out. For example I have a Pils now on its 17th day still with a 1/2 inch of kraeusen and a air lock bubble every 30 seconds. I know take a SG reading but it is still going strong.
I know there are many variables involved but mine just seem to take longer even my Ales.
Maybe I should not use my experience as advice but the lagers are turning out very good.

[quote=“DUNNGOOD”]Ken, I don’t know why but my Lagers seem to take longer to ferment out. For example I have a Pils now on its 17th day still with a 1/2 inch of kraeusen and a air lock bubble every 30 seconds. I know take a SG reading but it is still going strong.
I know there are many variables involved but mine just seem to take longer even my Ales.
Maybe I should not use my experience as advice but the lagers are turning out very good.[/quote]
Well, if the lagers are turning out good then you should keep doing what you’re doing. I’m definitely more patient with my lagers than my ales and I know that they will usually take a good 14-21 days, no matter what. The cooler temps has everything happening slower and the bottom line is that there is no need to rush it. I went to Vermont in 2007 for some biking with my wife and we were lucky enough to stay in Burlington for a couple of days, go to Vermont Pub & Brewery and actually sit down with Greg Noonan (RIP) and have a few beers. As we talked about making lagers (his passion) he told me that homebrewers were leaving their lagers in primary too long. I asked him what he meant and he said that every time he spoke to a lager-making homebrewer, they were leaving their lagers on the yeast for 3 or 4 weeks. I told him that it sounded standard to me. He said, “No, no… if you do everything right there’s no reason why a lager couldn’t be completely done in a week”. I went on to say that homebrewers don’t have the same quality control & gizmos that commercial breweries do and that homebrewers probably underpitched their lagers. He agreed that was probably true. Still, I don’t like to rush anything and I’d rather that the beer be done, d-rested and the yeast drop (for the most part) before I transfer it.

I use the Mr. Malty calculator for the pitching rate. I also pitch at 45-50F into well aerated wort. Lag times are 1-2 days and I get a nice active fermentation.
I have used water from other brewers that have shorter ( maybe normal ) times and still it seems to take my lagers longer.
I will go back and study my methods and reread Greg Noonan’s book. I always win medals at the BJCP contests and really like my beers. But it seems like we are always looking for better.
Cheers

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