Lager diacetyl rest?

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animalx

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Long time lurker, first time poster here. I finally got around to making my first Lager, a munich hellas. Original plan was to ferment from 1.054 to 1.02 at 49-50 degrees, do a diacetyl rest for 2 days at 60 degrees, then lager for 2 months at 35 degrees. However my OG was 1.06 and after 6 days I measured at 1.014 which should be my FG. Due to a surprise upcoming trip at the end of the week I have to leave this beer untouched for 9 days. Do you guys suggest I skip the diacetyl rest, do the diacetyl rest now, just wait until the end of the week and rack/lager or just leave it at 49 degrees until I get back? In the sample of it, I didn't detect any diacetyl only a very light sulfur taste, my overall impression was fantastic. I used wyeast 2124,starter, 1min oxygen, and some yeast nutrient.

thanks for the advice.
 
I would go ahead and do the rest now. I usually go up to upper 60's for a few days.

I've found with OG of 1.055 and fermenting at 50F, I usually hit 1.018 at around 5 days. I can almost tell by how much the kreusen has fallen and looking at the wort, but I always double check with a hydrometer.
 
Do the d-rest. Give it 3 days at 62*F.

When tasting it at this stage, you probably won't detect any butter flavor at all even if you have a problem. That's because most or all of the diacetyl precursor (alpha-acetolactate) hasn't converted to diacetyl. That happens later. At his point, some brewers can sense a slickness to the mouthfeel due to the acetolactate.

By doing the d-rest at the higher temp, you actually encourage that conversion and the yeast reducing the level to below that which is detectable.
 
I would probably do the diacetyl rest now. Leaving it out at d-rest temps (60F +/-) for 9 days won't be a problem. I frequently let my lagers sit at 60-65F for a week or more while I make space in kegs/carboys for lagering.
 
You can also run a quick test to see if the precursor is present. Prepare a hot water bath with water at about 150F and an ice bath. Take two samples in glass containers. Cover each with tin foil. Place one in the hot water bath and the other leave at room temp. After about 15 minutes remove the glass from the hot water bath and cool back down to room temperature in the ice bath. Now smell them. If the one that was heated an cooled now smells buttery you need a rest and more time on the yeast.
 
Thanks everyone. I am going to start warming it up now. I will test it on Thursday and either rack/lager or leave for 9 days at the warmer temperature.
 
Any recommendations for how long to cold condition a hellas? Right now it is 3 weeks at 35 degrees and I am running out of beer.
 
I typically lager 1 week for each 0.010 of OG. So if my lager is 1.060 OG to start I'll plan on 6 weeks. I have done as short as two weeks and the beer was still fine but definitely improved with continuing lagering.
 
Thanks begin2brew, I am going to go with your suggestion of 6 weeks. I am a little excited about my first lager.
 
You probably don't even need the d-rest, but it's safe to do it anyway. Like others said, just do a 9-day d-rest. I've made many many lagers, and only had a diacetyl problem once, and that was despite a 3-day rest at 65F. So I always do d-rests for 5+ days anyway; it can't hurt to run them longer as far as I can tell.
 
Well the lager came out pretty good, I can't detect any fermentation issues. Clean and Crisp! I did however mess up the bottling and only half the bottles carbonated. I should have stirred up my fresh yeast/sugar a little better. Live and Learn. Thanks for all the help everyone.
 
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