Diacetyl Rest and Lagering Question

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roto

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Hi,

I'm sure this has been answered before, however I could not find a definitive answer using the search feature, so here goes...

My first lager was in the primary at 50 degrees for 12 days. I increased the temperature to 60 degrees on day 12 for a diacetyl rest, and plan on moving to secondary for lagering on day 14. My question is... is it OK to transfer to lager even though there is still quite a bit of airlock activity (which increased after raising the temperature)? Or should I leave it at the elevated temperature until activity stops/slows?

Thanks
 
I say you take off and do a hydrometer reading. It's the only way to be sure.

Okay, "Aliens" meme aside, the airlock activity may just be a result of gas escaping/expansion as the beer warms. You should check the reading. My diacetyl rests are usually at room temperature for 24-48 hours, and then lagering (but for much more than 14 days. What did you brew?)
 
Thanks for the reply. I thought about taking a reading, but was thinking with all the activity in the airlock I was still far from being done with fermentation. I didn't think about activity due to temperature change...

I'm brewing Jamil's Extra Yellow from Brewing Classic Styles. I was planning to primary for 2 weeks, then lager at 38 degrees for 4+ weeks.
 
Ideally, you should be in primary until you reach 75% of expected FG.

For example, if OG is 1.05, expected FG is 1.01, you would start the diacetyl rest once gravity reached 1.02 (1.05-1.01=0.04............0.75*0.04=0.03............1.05-0.03=1.02).

A two-day diacytl rest then easily gets you to FG.

In your specific case, the airlock activity in secondary is probably a combination of the last few gravity points and just off-gassing due to the temperature bump. No big surprise, but DEFINITELY take a gravity reading and make sure you are at expected FG before you start lagering. You should expect it to take a good 48 hours to complete the diacytl rest and wax off the final few gravity points before you move to lagering.

Good luck!
 
Just took a hydrometer reading... OG = 1.061, Current gravity = 1.020, Estimated FG = 1.013 So...

Looks like I started the DR too soon. Now my question is:

Do I leave at the elevated temperature until it's done (already at this temp for 48hrs) or do I drop the temperature back down to 50 degrees to finish fermentation?

Thanks again
 
Just leave it in your DR rest until it's done, and you'll be fine!

Yep. Lowering the temp on the yeast at this point will probably slow them to a crawl if not make them completely settle out. I'm betting you'll get to FG in a day or two at the higher temp.
 
Thanks for the help. Took a hydrometer reading yesterday and I had finally reached FG, so I transferred to the secondary. Now my question refers to lagering. My initial thought was to lager in a keg under minimal pressure (disconnected from the CO2), however decided to lager in a carboy at the advice of the guy at the LHBS. However, now I'm concerned there is too much head space in my 3 gallon better bottle:

photo(2).jpg
 
roto said:
Thanks for the help. Took a hydrometer reading yesterday and I had finally reached FG, so I transferred to the secondary. Now my question refers to lagering. My initial thought was to lager in a keg under minimal pressure (disconnected from the CO2), however decided to lager in a carboy at the advice of the guy at the LHBS. However, now I'm concerned there is too much head space in my 3 gallon better bottle:

When in doubt avoid another transfer. Its cold enough to not have to worry much about it.
 
Yooper, would you just carb it enough to seal the keg and bleed off the oxygen, or would you put it under carbonating pressure and leave it there until I'm done lagering?
 
Yooper, would you just carb it enough to seal the keg and bleed off the oxygen, or would you put it under carbonating pressure and leave it there until I'm done lagering?

I'd probably go ahead and carb it up while it's lagering. The carbonating will not affect the lagering (which drops polyphenols primarily).
 
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