Fermentation Temp Adjustments

Hi all,

I've got an American brown ale that has been fermenting for about 4 days now. It started around 68 degrees, but it was surprisingly warm where I live the last 2 days and the temp hit 75.

I adjusted it this morning to get it back into the proper range. My question is if I should be worried about the few days it spent above 70 degrees early in my fermentation.

Thanks for everything!

 

I wouldn't worry too much about a couple days at a higher temp. I've had that happen with some of my ales in the summer months (when I've been neglectful about checking in on it each day). While this may not apply all the time, but it's been my experience when that happens that using a secondary to let the beer condition for an extra couple weeks has helped. Or at least it's helped me feel better about it

 

What yeast?

If you're using US-05 (or most ale yeasts, in my experience), then yes, 75 is too high. The good news is that the temperature is really only critical for those first 3-5 days. After that, it doesn't really make much difference. The bad news, in your case, is that even 68 is too warm (for US-05 or S-04, at least, probably most others too). The sweet spot is 63-65° F. Also, note that this is the beer temperature, not the ambient temperature. Actively fermenting beer can be up to 10° F warmer than the surrounding ambient air temperature.

Finish it up and taste it, see how it turns out. I suspect that you'll find it exhibits a prominent "Belgian" character, so it would still be drinkable. If it fermented much warmer (75+° F), you'd notice the harsher fusel alcohols. Take it as a lesson learned. The single most important factor in producing good beer is temperature control. For ales, keep that temperature at 63° F for the first 3-5 days.

 

Yeah, I am using US-05. 75 degrees was as warm as it got (that is the wort temp, not the ambient temp).

It was below 70 yesterday so it was in that range for no more than 24 hours (the 4th day).

Right now the wort temp is back at 69. I'm hoping to stabilize at the right temps for the rest of the process. Thanks for the input.

 

Eh, whatever.... it's too late now and I'm sure it will be fine. Don't worry. Those first few days are key.

 

Right. Good to know. Will be nailing the temps on the next batch. This was round 1 so there was some fidgeting with the temps in the fermentation room trying to get it right and it just got away from us a bit.