Diacetyl rest of lager

[DarrellQ]

Oops! Typed first version of this before first cup of coffee! I brewed an Octoberfest lager last Thursday and 12 hours later had very vigorous fermentation at 59 49 degrees using White Labs Octoberfest/Marzen liquid yeast. It went very strong for 6 days and then started to slow down. I then bumped the temperature up to 69 59 degrees for diacetyl rest and yeast activity became vigorous again. Should I take the temperature even higher for diacetyl rest? Once that is finished, should I lager it for several weeks in the primary or rack it over to my keg for lagering at 35 degrees? Appreciate your comments!

 

[dmtaylor]

Leave it at 69 F until it seems finished, then hold there for a few more days. Then you can drop it to 35 degrees to lager it if you wish. About a month of lagering should improve it.

 

[Craiginthecorn]

What gauge are you using to determine that there was increased yeast activity? Changes in SG? Bubbling airlock? Kräusen? If bubbles in the airlock, it may be just expansion of gas and release of dissolved CO2 due to the rise in temperature. dmtaylor’s advice is sound. I’ll note that diacetyl can be cleaned up at surprisingly low temperatures provided that yeast is still in suspension. 69F is higher than needed, but shouldn’t e a problem.

 

[Beermeister32]

Better to chill it in the keg.

If you chill the carboy, the temperature drop can cause a slight vacuum which sucks air into the carboy. You want to minimize O2 exposure to your beer.

Work towards reducing O2 exposure at all steps.

 

[DarrellQ]

Better to chill it in the keg.

If you chill the carboy, the temperature drop can cause a slight vacuum which sucks air into the carboy. You want to minimize O2 exposure to your beer.

Work towards reducing O2 exposure at all steps.

Thanks! Yes, I do a direct transfer to keg with no O2 exposure and since I use a modified Fermonster, I put about 3 lbs of Co2 on it while cold crashing to keep it from collapsing.

 

[wsmith1625]

Oops! Typed first version of this before first cup of coffee! I brewed an Octoberfest lager last Thursday and 12 hours later had very vigorous fermentation at 59 49 degrees using White Labs Octoberfest/Marzen liquid yeast. It went very strong for 6 days and then started to slow down. I then bumped the temperature up to 69 59 degrees for diacetyl rest and yeast activity became vigorous again. Should I take the temperature even higher for diacetyl rest? Once that is finished, should I lager it for several weeks in the primary or rack it over to my keg for lagering at 35 degrees? Appreciate your comments!

I have a Marzen on tap right now and also used WL820 yeast. It was my first time using this yeast and I had a ton of diacetyl. Took around 2 weeks to clean up. Make sure you taste it before you start lagering.