Wort Temp

[madz1980]

Hi,

I bought an aquarium Thermometer (submersible) to know exactly the wort temperature during first Ferm.

People always told me that the room temp and the wort would be really different.
I'm brewing a regular pale ale, using us-04 yeast. The room temp was at 19C and the wort was the same. After 36h of high yeast activity, the maximum temp reached is 21.8... We are talking about only 2C difference with the room temp... It's not that big... So, if it's almost the same for every wort/yeast, 3 degrees is not that bad... stop freaking out guys ;-)

Any similar experience to see if I'm not wrong?

Thanks for sharing!

MA

 

[oceanic_brew]

Well I'm making a batch of beer now with Wyeast 1968. I've never used the yeast before but I've been recommended to keep it at 64 for the first few days with a slow rise to 70.

Apparently it's a very finicky yeast temperature wise and I guess after some experimentation I could rely on only room temp provided that the relation between room temp and fermentation were the same for every batch.

With a hef I've been brewing, the difference of 3 degrees has produced either the banana that I hate or the clove which I love.


Also for repeatability it's nice to know exactly what your beer temp was. Might not be an issue for some but depending on where in my brew room my fermentor was during the first few days it could be a drastically different temperature.

I can set my room temp to 70 and still measure 66-64 in some spots in the room.

I guess the recommendation of measuring the beer temp rather than ambient is a safe one considering there are so many variables and anomalies; aggressive fermentations, aggressive yeasts, volume, wort density, placement of fermenter in the room, convection of air, are ones that come to mind but I have no idea if these are actually factors.

I can only imagine the continuous posts on here from new Brewers asking how much lower their ambient temp should be and for long, and how do you know for sure?!! On and on ...

I know some yeasts I've worked with would not produce an appealing flavor at 72 but did just fine at 68-69.

Your one experience only justifies controlling only your room temperature to your one experience with that particular beer and that yeast.

Good one for the XBMT's!!! Maybe it's been done?

 

[JawZziff]

I do small batches and I find I get about 2-3 c difference than ambient if it's a stronger ferment. just like oceanic brew said, so many variables. you'll probably be ok.

 

[chickypad]

I agree with oceanic. You're talking 66 vs. 71.2 farenheit, which IME does make a difference for some yeasts. WL001 for example I don't like at 71-72. But there's too many variables as mentioned to apply one data point to all fermentations, I've personally seen at least an 8 deg farenheit difference ambient vs. wort. I'm not freaking out, but I'm not giving up my temp direct control.