What temp does lager yeast stop fermenting?

[ahwinney]

I brewed a doppelbock in the hopes of cold fermenting it in my garage. I pitched the yeast at 68F, made a starter 24hrs in advance, and am letting fermentation begin at 68F for the first 24hrs. I want to the then store it in my garage, let the temperature lower, but I'm concerned it's too cold. I'm using WL Oktoberfest/Maerzen yeast. The weather also took a turn for the colder for the next two days. I know there are styles where people ferment at ale temperatures using lager yeast, but I was really hoping to get a true, or at least truer, to style lager. Does anyone know at what temperature lager yeast stops fermenting? Any other advice is welcome.

 

[Mike_kever_kombi]

68 is blazing hot for a lager yeast. I lager in the 50-54f range.

A lot depends on the yeast strain, but 45 is about the bottom end for fermentation temps.

 

[ahwinney]

That's true. I know the california common ale is brewed with lager yeast at ale temperatures, but that's not really what I was going for. I may have to leave it for a couple days anyway, considering it's probably cold enough to stop fermentation right now. Hopefully it turns out well, I'm planning on converting a chest freezer soon, so if it's not good I can always make again the right way.

 

[wailingguitar]

Depends on the yeast strain and the conditions. I have had active ferments in the upper 30's. This was achieved by a slow, steady ramp down of temp a few degrees per day, the beer was exceptionally clean and crisp. I often ferment lagers in the mid 40s, again, ramping temp down after starting about 58-60F

 

[Cyclman]

I start my lagers low, then ramp up to 50 ish. Below 40, not much yeast activity will occur, they'll floc out.

 

[JayDubWill]

Depends on the yeast strain and the conditions. I have had active ferments in the upper 30's. This was achieved by a slow, steady ramp down of temp a few degrees per day, the beer was exceptionally clean and crisp. I often ferment lagers in the mid 40s, again, ramping temp down after starting about 58-60F

I can second this. I just kegged my American lager and it dropped another 2 points sitting at 37F for a month. It's now at 1.008 and mighty good. I also do a slow ramp down from D-rest temps.