Question about Diactyl Rest

Hi all,

I am attempting my first lager and had a question about the diactyl rest. This is the Standard Lager kit from Austin Homebrew Supply and I have had great success with other brews and feel like their instructions are top notch.

For this lager, I have followed the direction of pitching my Liquid American Lager Yeast at 70 degress and then brought the primary bucket into my bulkhead (consistent 40 to 50 degree temp) for 10 days. I have brought the primary up to a 72 degree area on Monday (10 days later) and planned to take a gravity reading tonight (48 hours later) and transfer to a glass carboy.

My question is this; once I brought my primary up, within about 8 hours the airlock started to bubble like crazy. From what I understand about a diactyl rest, this is a good sign that the yeast is 'eating the diactyl' it orginally produced. It is still bubbling away and I am concerned about taking a reading and racking if this is going on.

The directions say to transfer to a secondary and cool the carboy down for another three to four weeks. Should I wait until 'visible signs' of the diactyl rest have slowed before doing this, or is it ok to go ahead a rack and lager? I am just worried about leaving the beer in the primary at 72 degrees for too long.

Thanks for any advice!

I've never had noticeable airlock activity during a diacetyl rest...

I wonder if your fermentation stalled. Probably should've taken a gravity reading before warming it up. I do d-rests on my lagers at about 80% of the target FG.

It could be finishing up fermentation, but it could also be the co2 in the beer coming out of solution. Cold liquids "hold" co2, and when it warms up, the co2 is released more readily. When I pull my lagers out of the lagerator (I don't usually do a diacetyl rest, since I pitch cold), the beer is actually partially carbonated because of the co2 in the cold temperature. I think that's what you're seeing- but I'd check the SG to ensure it's done, then start the lagering. If it's not completely done, let it finish up and then lager it.

Thanks Yooper. That is what I was thinking.

I was hoping you would answer this! You rock!

Yeah, when I went to keg my Alt last weekend (I had been "lagering" it at 45*), it started bubbling away. I had not seen any airlock activity in a long time. I figured it was either CO2 in solution, or trapped in the yeast cake being released.