Maintaining ideal fermentation temperature

[Vrtigo1]

I've read that 65 deg is a good starting point as far as fermentation temp for most ales. I've got a freezer with a Brewers Edge temp controller that I plan on using to maintain the temps as my ambient temp here in Florida is way too hot. My question is, do I need to control the temperature of the actual wort in the fermenter, or the ambient temperature outside the fermenter? I ask because I have seen people say that the fermentation process itself can raise the temperature of the wort by a non-trivial amount so if I have the temp controller's probe sitting in a glass of water inside the freezer then I'm maintaining the "inactive liquid" temp at 65 degrees, but the wort is likely to be warmer than that due to the activity going on in the fermenter. I can't think of any way to actually monitor and control the wort temp, but just wondering if anyone has any feedback on this topic.

 

[kombat]

You should control the actual temperature of the beer inside the fermenter. The best way to do that is with a thermowell.

 

[pricelessbrewing]

Tape the temp probe to the outside of the fermenter. Cover the temp probe with a towel or piece of insulation foam. Set temp controller to intended temp.

Each yeast and recipe will have a specific fermentation temp. This is most important in the first 3 days or so of fermentation, after that you can increase the temp by a couple degrees to ensure it finishes quickly and cleanly without causing the yeast to flocc early like some english yeasts like to do. When fermentation is complete, leave it for a day at 72F. Then if you can, cold crash it for two days with a post fermentation fining agent like gelatin of bioclear.

 

[slym2none]

Yeah, when we talk about "keep the beer at 64° F", we mean keep the WORT at that temp. In the beginning part of fermentation, wort temps can be more than 5 degrees above ambient. After it drops off, it can be close, and by the end of 14 days, ambient & wort temps can be the same. This takes monitoring of the wort & periods of the ferment.

 

[Vrtigo1]

Thanks guys, for the information.