Ideal Temperature for Primary, Secondary & Bottling

I'm trying to get a handle on how temperature affects beer at different stages in the process. Either way, I'm thankful the li'l yeast seem to be pretty flexible in working with me.

For those much wiser than I, a few questions:

Primary (fermenting): Let's say you have a yeast that has an optimum fermentation temp of 68 - 73 degrees. Will the final beer flavor change if I ferment at 68 vs. 73? Or, does this just mean that the fermentation may take longer at the lower temperature? I understand that for some beers styles like a Hefe, you may want to ferment higher to get some of the fruity esters.

Secondary (clearing): Let's say you're not cold crashing. You are just going to secondary for a couple weeks at a temperature close to your fermenting temperature. So, if we fermented at 70, will there be a flavor difference if I let it sit at 60 degrees vs. 70 degrees vs. 80 degrees? Does temp matter at this stage since fermenting is pretty much complete at this point and we're just letting stuff settle out?

Bottling (conditioning): Since we still need the yeast to carbonate our beer, assuming an ideal range of 68-73 for fermenting:


Cheers in advance for wading through this post!

Primary: It definitely depends on the yeast, but if I want the beer to be as clean as possible, I would ferment at the lower range. e.g. I use nottingham and Safale-05 and try to keep my temps down in the 65F range. This is the most important time to keep your temperatures under control, because this is when the yeast are doing the majority of the work and the higher temperatures can produce unwanted off-flavors.

Secondary: Don't do it, but temperature control is not as important in this step, but you still may want to avoid the higher range just in case those yeast are still working in there.

Bottling: I keep it at around room temp, so between 65-72. Again temperature control is not as important in this step. When I bottled it was usually perfect after about 2.5 weeks.


So really in my brewing I've found that if you control your temperatures for the first couple of days of fermentation, you are pretty much set. Not saying to not be aware of it afterwards, but that is when the higher temperatures can do the most damage to your beer.

tmoney1224 has it right, the only thing I would add is about the secondary, temp is not as important to a certain degree. For example if you are dry hopping in a secondary, you don't want it to be 85 degrees. In a perfect world the whole process would be done between 60 and 70. If you cold crash though this will change the bottling temp obviously.

Thanks for the quick responses, this is extremely helpful.

I had a bit of stumble with my most recent batch. Pitched the yeast into wort that was right around 70 degrees, but then, that evening outside temps plummeted and my room temp took a dive to 64-65. I was a little concerned, so after about 24 hours, I warmed up the room to around 72 using a space heater, gave the wort a little stir to get the yeast up from the bottom and then closed 'er up. Yeast started going nuts withing 12 hours or so and I kept that room at around 72 thereafter.

I'll try to shoot for a bit on the lower side next time 'round.

Any thoughts on if the yeast would have kicked in at a 64-65 temperature eventually on their own (White Labs California Ale)? I was just afraid I shocked it to a long sleep if I didn't get the liquid a bit warmer.

----------------------
WLP001 California Ale Yeast
Attenuation: 73-80%
Flocculation: Medium
Optimum Fermentation Temperature: 68-73 °F
(20-23 °C)
Alcohol Tolerance: High
----------------------


Thanks again!

I believe Duvel bottle conditions at 80F and they go to great care to make sure every bottle is the same temp. Yeast strain may have something to do with it. Almost all mine condition at ~75F or slightly higher and I've had no problems. Always fully carbed in one week.