When is the most critical time to control fermentation temps

If memory serves, I believe that is is in the first 48-72 hours of pitching yeast. This is when they are most active in producing phenols, fusels, esters, etc., and if you want to minimize those, make sure to keep a ‘leash’ on the yeast by regulating the fermentation temp. I do this with a temperature controller probe insulated with styrofoam, duct-taped to the outside of the fermenter.

I ask the question because I only have room for two vessels in my fermentation chamber/lagering fridge. Currently, I have a California Common in there, and the yeast was pitched Saturday night @ 9pm (pitching + 84 hours at the moment) at 64 degrees. The yeast is actually Wyeast 2204 Bavarian lager.

I have a bit of an aggressive brewing schedule coming up. I am planning on brewing a hoppy american wheat tonight, THEN I am brewing an Oktberfest with my wife on Sunday. Bottom line, I need to have the Oktoberfest set to 50 degrees on Sunday, meaning that the ferm fridge will likely have a lower ambient temp.

My current plan is to brew the wheat tonight (estimated OG of 1.051), pitch a stepped-up US-05 starter (as I need a quick and vigorous fermentation, this wheat is going to be kegged in 12 days) at 66 degrees, then on Sunday (pitching + 4 days), remove the wheat, leave it in the basement (ambient temp of ~74 degrees) to finish up.

The only issue with this plan is that I would need to remove the California Common tonight, as if I tape the probe to the wheat, the freezer will likely get down really low to try to stabilize the fermenter temp AND I would need to do the same with the wheat to make room for the O-fest.

Clear as mud? I’m just trying to minimize unwanted esters, phenols, fusels, etc., and was hoping that I could let these fermentations go after a few days. Alternatively, I could rig up the swamp chiller.

I am not sure you can just this by hours as much as activity and gravity readings. Unfortunately.

I always try to wait until the bubbling activity stops or slows waaaaaay down before pulling out and finishing at ambient temps.

But, I am with you on trying to coordinate this. After I moved in March, I had to take several months (4-5 total) off of brewing while I got things set back up. I have been brewing lots of ales getting my pipeline back in check when I realized that I was behind on an Octoberfest. Since I needed to do a lager, I decided to do several and am juggling how to sneak a couple more in before I just back into ales as I need to get a Pumpkin Ale going pretty soon.

So many beers to brew and so little time!

[quote=“560sdl”]I am not sure you can just this by hours as much as activity and gravity readings. Unfortunately.

[/quote]

Agree.

2-3 days after a good krausen has formed might get you in the ball park.

But sense it may take up to 3 days for active fermentation to start, I don’t think you can say “48-72 hours after pitching”

The 1st few hours/days the yeast are reproducing and getting ready to party. Let them have some fun before you change the environment.

[quote=“560sdl”]I am not sure you can just this by hours as much as activity and gravity readings. Unfortunately.

I always try to wait until the bubbling activity stops or slows waaaaaay down before pulling out and finishing at ambient temps.

But, I am with you on trying to coordinate this. After I moved in March, I had to take several months (4-5 total) off of brewing while I got things set back up. I have been brewing lots of ales getting my pipeline back in check when I realized that I was behind on an Octoberfest. Since I needed to do a lager, I decided to do several and am juggling how to sneak a couple more in before I just back into ales as I need to get a Pumpkin Ale going pretty soon.

So many beers to brew and so little time![/quote]

Truth, I meant to take a grav reading on the steam last night, maybe I can do it @ lunch today and figure out my schedule.

One thing I didn’t plan for with my setup is that when brewing a lager (and during the 4-5 weeks of lagering), I will not have fermentation temp control if I want to do additional lagers. Curses!

[quote=“Nighthawk”][quote=“560sdl”]I am not sure you can just this by hours as much as activity and gravity readings. Unfortunately.

[/quote]

Agree.

2-3 days after a good krausen has formed might get you in the ball park.

But sense it may take up to 3 days for active fermentation to start, I don’t think you can say “48-72 hours after pitching”

The 1st few hours/days the yeast are reproducing and getting ready to party. Let them have some fun before you change the environment.[/quote]

Hoping the lag phase will be short on both since I borderlined overpitched on the steam and will likely be doing the same for the wheat. Going to be tight, but will post an update on my gravity readings.

Do you typically want to do an increased temp (ie for a diacetyl rest) AFTER the beer has hit terminal gravity, or just when ‘signs of active fermentation’ (ie those bubbles/airlock farts that we homebrewers take so much comfort in) have slowed?

http://www.brew-wineforum.com/viewtopic ... 08&t=59851

This will be my procedure for brewing lagers after I get my moving finished.

But opinions are like… :wink: