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Question on diacetyl rest

So, I have a batch of Bavarian helles that I’ve been fermenting for about 2 weeks. I transferred the primary from my cooler to my basement for a DA rest last Saturday; the ambient temp of which is about 60 - 63 degrees. I know a normal DA rest only needs to be about 4 - 5 days, but I figured the lower temp in the basement may merit a bit more time for the yeast to clean everything up.

Is my reasoning correct on this one? If I racked and brought it down to lagering temps this weekend would I be alright?

Also, as a side note, I plan on brewing a batch of Czech Pils this weekend, and will be fermenting in the same cooler that I’ll be lagering my Helles. I think I read that lagering temps should be lower than primary fermentation temps for lagers, so at what temperature should I lager my helles and ferment my pils simultaneously?

Any help/advice is as always appreciated. Prost!

To my knowledge it is generally recommended to do the diacetyl rest at approximately 15 deg. higher than primary fermentation, and to lager at about 10 deg. lower than primary fermentation. I think optimal primary fermentation range depending on the strain, is about 45-48 deg.

So if my primary fermentation temp for the helles was 48 - 50 degrees, the 60 - 63 degree DA rest temp may or may not be high enough? I could move it upstairs for another couple of days, where the ambient temp is around 74, but I’m not sure if it would be too high.

If I tasted a sample before racking, would it be pretty obvious if the diacetyl has been cleaned up? I know DA leaves a buttery off flavor, but having never tasted it personally yet, I’m not sure how pronounced it may or may not be.

The exact temp of a d rest doesn’t matter. The reasoyou do it is to make the yeast more active so they consume the diacetyl. As long as the temp is high enough for that, the exact number makes no difference. And FWIW you may not even need one. Only a very small number of my lagers do.

+1 The temp you did your D rest at is just fine especially if you let it ride for 5 days, and most don’t really need a D rest in the first place.

The bad news is that the ideal temp for lagering is pretty close to freezing, which is obviously not conducive to fermenting. I lager my beers at 32 degrees for 5 weeks, but I have heard of people doing them at 50 for a few months with pretty good results. Just be careful, because depending upon the yeast strain you’re using, you will get a stuck fermentation if you push it too low on the temperature during fermentation. I also pitch twice as much yeast in a lager than I would for a standard gravity ale. That sour green apple taste and smell in your beer from a stuck fermentation really throws a turd in the punchbowl on bottling/kegging day.

To be honest, I wouldn’t really recommend trying to lager one beer and ferment another one at the same temperature. I know it’s a pain in the arse, and we all want to drink our beer as soon as possible. But if you’re going through the trouble of making lagers (and your Helles is a damned fine one), I would be patient, and do one at a time properly if you only have one freezer.

Lagers are worth the extra wait and trouble IMHO.

+1 The temp you did your D rest at is just fine especially if you let it ride for 5 days, and most don’t really need a D rest in the first place.

The bad news is that the ideal temp for lagering is pretty close to freezing, which is obviously not conducive to fermenting. I lager my beers at 32 degrees for 5 weeks, but I have heard of people doing them at 50 for a few months with pretty good results. Just be careful, because depending upon the yeast strain you’re using, you will get a stuck fermentation if you push it too low on the temperature during fermentation. I also pitch twice as much yeast in a lager than I would for a standard gravity ale. That sour green apple taste and smell in your beer from a stuck fermentation really throws a turd in the punchbowl on bottling/kegging day.

Thank you both for the advice. How’s this for an idea, I start my Czech pils and leave it in the primary for two weeks to ferment at recommended temps, along with my helles. After primary, I bring the temps down to lagering temps for my helles, and let rest for an additional four. The extra two weeks at 48 -50 degrees shouldn’t adversely affect the helles should it?

I didn’t “lager” my last lager at all. I left it in primary at about 50 F for like 5 weeks and called it good. Turned out great. I’m going to enter into competition and I expect it will score mid to upper 30s. (I’m a judge so I can say that… I am only slightly biased.)

As for the D rest… time and temperature don’t matter too much. 3 days, 5 days, 14 days, doesn’t matter. You can always just lager it in the keg or the bottles, too.

[quote=“dmtaylo2”]I didn’t “lager” my last lager at all. I left it in primary at about 50 F for like 5 weeks and called it good. Turned out great. I’m going to enter into competition and I expect it will score mid to upper 30s. (I’m a judge so I can say that… I am only slightly biased.)

As for the D rest… time and temperature don’t matter too much. 3 days, 5 days, 14 days, doesn’t matter. You can always just lager it in the keg or the bottles, too.[/quote]

I don’t think it would affect your Helles in an adverse way at all, as dmtaylo2 mentioned above (and I do trust his judgment because he has helped me out on a few occasions, with a Helles as a matter of fact, with excellent results).

I do, however, feel that a nice, extended very cold lagering period (whether in secondary, keg, or bottles) will definitely improve your beer’s clarity and smoothness. My Helles came out absolutely wonderful with the exception of me overshooting the color very slightly, and undershooting the biscuity aroma and taste I wanted very slightly. But she’s as smooth as a baby’s bottom, wonderfully malty with a very good slight hop balance, and a beautiful pure white head. It’s getting hot here in Florida, and this Helles is perfect for it. It actually makes me want to mow the lawn :smiley:

Sorry, got sidetracked… Your Helles will be just fine doing what you’ve mentioned. What a great beer style!

:cheers:

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