Diacetyl Help

[rasherb]

I finished my diacetyl rest (24hrs) on a lager and started ramping the temp down to 2C. I tasted it today and there was still a lot of diacetyl character. Should I raise the temperature back up for more resting time? Yeast is WLP 830.

 

[Yooper]

I finished my diacetyl rest (24hrs) on a lager and started ramping the temp down to 2C. I tasted it today and there was still a lot of diacetyl character. Should I raise the temperature back up for more resting time? Yeast is WLP 830.

Yes, if you haven't racked it yet bring it back up to diacetyl rest temperatures. If you've already racked, you may need to make a yeast starter.

 

[homebeerbrewer]

How long has it been fermenting? I typically ferment my lagers for 6 weeks before I even check gravity/taste. I try to keep it at a constant temp for that long, and if the gravity/taste test is good, I chill it.

 

[rasherb]

Attenuation is a lot lower than I expected too. It started at 1.042 and is now at 1.012 after three weeks.

 

[Airborneguy]

At what point in the fermentation did you start the rest? You may have allowed the fermentation to proceed too far before starting it. That is a common mistake.

 

[rasherb]

Have not racked it yet, fortunately. I'll bring it back up to d-rest temps (64 sound good?) for a while. Maybe a week?

 

[rasherb]

12/42 = about 70% attenuated. Did I wait too long?

 

[usfmikeb]

I don't have an extensive lager history, but the best practice here is to increase up to the d-rest temp before fermentation is finished, so that the yeast are active when they go into this phase.

 

[rasherb]

It was about 2-weeks in primary when I started the rise to d-rest. 24hrs D-rest. Then I take it down from there 2 degrees C per day. It's at 2C right now, but I just shut off the temp control so it should free rise back up to room temp (68-64 F).

 

[Airborneguy]

1/3 left is a little better, but you're just over that so I'd say that's not the problem.

 

[osagedr]

Good lesson for others to learn from--don't start to lower your temperature before the diacetyl is gone.

 

[rasherb]

I checked yesterday and the Diacetyl was gone. So that's about 5 days at 64-66 degrees F. Maybe if I checked earlier the Diacety would have been gone on day 3 or 4..

Time to descend to lagering again...

Thanks for the help everyone!

 

[osagedr]

Awesome! Nice when it's an easy fix.

 

[shadows69]

I always do a 3 to 4 day d-rest after 10-12 days of primary before doing the transfer to secondary. Of course taking readings is a sure fire way but I'm lazy I guess and never had a problem so far, knock on wood.