Diacetyl rest - Am I too early?

Hey All,

So it's been 2+ weeks since I brewed the Classic American Pilsner in the most recent issue of BYO. I've kept the temp at a nice 50-55 degrees for the Pilsen Lager Yeast by WL. The airlock activity stopped a few days ago, but there still is a nice thick head of krausen on my brew. I decided it was time for the diacetyl rest, so I raised the temp up to 62 degrees and am going to leave it there for a few days.

Am I too early in raising the temp because of the krausen, or is this the right time as fermentation is most likely slowing down but still active?

I haven't done a gravity measurement yet, but once I have I will post it.

Use your gravity reading next time before initiating your D rest. Airlock activity and visual inspection of the krausen are meaningless.

I think you might be too late for diacetyl rest. You need to check gravity and not go by time or airlock bubbles

You are too late if anything, but it's impossible to know without a gravity reading. The good news is that you probably didn't need one, and even if you have diacetyl, it is possible to fix it.

Next time keep your hydrometer involved in the process.

Okay, current gravity is 1.011 using my hydrometer, so it'd say it's pretty much done. But there is still a LOT of suspended yeast and the krausen is still pretty significant. Would you continue with the diacetyl rest, or would you not bother and drop it back down to 50 degrees?

I used White Labs WLP800 for this one. Tastes pretty good, though. No buttery diacetyl taste.

Leave it. Nothing to be gained by going to 50 degrees. The krausen may or may not drop by itself. You can stir it down if you like. Once everything has fallen to the bottom and you are certain you have achieved FG (same reading three or four days from now), rack it to a secondary and start your lagering. Purge your secondary with CO2 before racking if you are able. Lower the temp slowly if you like, or just crash it. I've done both with good results.