Suppressing Temperatures During Vigorous Fermentation

[paulgobble]

I keep my fermentors in a cool closet in my basement. Ambient temperatures in there range from low 60's in the winter to 67º in the summer. During fermentation I have my fermentor sitting on a heating pad attached to a temperature controller with the thermo-probe inserted into a thermowell submerged into the wort/beer. So for the most part I have really good control of my temperatures during fermentation. I can set 68º and my system can maintain that temp.

Except during the initial vigorous stage of fermentation.

During my most recent brew, the target temperature called for by the recipe was 68º, the ambient temperature was 65º or 66º, the heating pad set to maintain 68º, but the heat generated by the vigorous fermentation kept the temperature in the fermentor as high as 71º. Thats 5 or 6 degrees above ambient.

Should I be trying to suppress the temperature in the fermentor during the vigorous initial stage of fermentation to keep the temps at my target temp? How would I do this? When a recipe calls for a specific temperature, is it understood that the temps will go higher during the initial stages? Or, since the yeast is the most active during this initial stage, is it even more important to keep the temperatures under control at this critical time?

 

[jack_a_roe]

whats the top end temp of the yeast/what yeast are you using? if it's not too far on the high end i'd let it ride. i've had some issues that i just rode out...even waaay more towards the top. then again i hopped the bejesus outta it...../drunk post

 

[paulgobble]

For the brew mentioned in the example, it was White Labs WLP002 English Ale Yeast. The stated optimal temperature range is 65º to 68º. So I went over by three degrees on the second day fermenting when it was at its most active.

And while I am concerned about this particular batch, my question was more about best practices. Every time I go to ferment a brew I run into this same situation - everyone must. To keep my yeast happy and keep consistent with my recipes what should I be doing when the yeast activity is pushing the temps up as much as 6 or 7 degrees?

 

[kh54s10]

Three degrees is, IMO, not enough to worry about. I ferment in my basement, which is heated during the winter and gets into the mid 70's during the summer. I built a fermentation chamber and COOL most brews year round.

It seems to me that you will be OK in the winter but will be on the high side in the summer. The best would be a dual controller that controls cooling and heating.

 

[Ilan34]

If you're not going to go the dual temp control route (which would be best if you have the space and money), I would suggest pitching as low as you can (maybe 2-3 degrees below the optimal fermentation temperature) and hoping it doesn't rise above the recommended max temp.

For example, if a yeast's recommended range is 64 - 69, chill your wort to 62 and pitch. During the lag stage and first 24—72 hours, it's vital to keep temps within the yeast's recommended range - after that, it's not nearly as important if it gets too warm. In fact, it's beneficial to allow it to rise to 68 - 72 before you package so the yeast can clean up.

 

[Cyclman]

A frozen water bottle next to the carboy, or multiple ones, can bring it down a bit- keeping it in contact with the carboy glass.

 

[hunter_le five]

If you're not going to go the dual temp control route (which would be best if you have the space and money), I would suggest pitching as low as you can (maybe 2-3 degrees below the optimal fermentation temperature) and hoping it doesn't rise above the recommended max temp.

For example, if a yeast's recommended range is 64 - 69, chill your wort to 62 and pitch. During the lag stage and first 24—72 hours, it's vital to keep temps within the yeast's recommended range - after that, it's not nearly as important if it gets too warm. In fact, it's beneficial to allow it to rise to 68 - 72 before you package so the yeast can clean up.

+1 Start low, and rise up to your ideal temp range.

the heating pad set to maintain 68º

The stated optimal temperature range is 65º to 68º.

Don't start towards the top end of your range, of course it's going to get too warm unless you are actively cooling it.

I generally start low and hold on the low-to-mid end of the range, and only let it warm up as fermentation begins to wind down, but I generally try to minimize esters, so this really depends on the style and flavor profile you are going for.

 

[SpeedYellow]

I'm surprised nobody mentioned this yet, but apparently a wet t-shirt draped over the carboy and maybe a fan can help you cool by a couple degrees. Next step up would be a swamp cooler, I.e. a big plastic bucket filled with cool water that you periodically add frozen ice bottles to. Next step is a ferm chamber, which is the way to go.

But you're right that if the target is 68f, then you should have 68f throughout the entire fermentation, especially at it's peak.