Fermentation temperature inside fermenter

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bloke

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I have never really logged the temperature of the fermenting beer inside the fermenter before. And it really surprized me how much higher it was during high krausen. Almost 5 degrees celcius.
I use to adjust the temp in fridge to right fermenting temp. But now I understan that I have to get an diptube to get the fridge to keep the beer at right remperature.

I know many of you are doing this. Have you ever logged the beer temperature during the yeast most active period? Do you manage to keep it in the right temp during this time of fermentation? Or does it matter if it gets a bit high?
My beer taste very good, but maybe they could be even better:)
 
I tape my temp probe to the side of my fermenting bucket then put a koozie over the probe to help insulate it from the air. This way I can monitor the beer temp instead of the air temp.
 
The difference in temp from the middle of the fermenter to the outside has been measured to be about half a degree F., not enough to justify a themowell. You do need to control the beer temp, not the air temp so having a controller with its probe taped to the fermenter will get you better results than just adjusting the refrigerator temp.
 
Putting the temperature sensor inside the carboy can work poorly. It might seem ideal, but you're likely to overshoot your target. You're also likely to freeze anything else in the freezer, as well as the airlocks. As mentioned above, the best point is the outside surface of the carboy.
 
I have not run this experiment myself, but I know others who have measured roughly 5 degrees F higher in the center of the fermenter than the ambient, so that we homebrewers need to account for this especially when comparing with temperatures provided by commercial brewers who are able to measure the temperature more directly. In other words, if XYZ Commercial Brewery recommends fermenting at 68 F, they might really mean 63 F ambient for us homebrewers to account for the heat rise to 68 F that will actually occur inside at high krausen. And of course, this is all a guess as it would be extremely difficult to learn exact numbers of one vs. the other.

It is almost always the safest bet that...

When in doubt, aim low. Aim real low.
 
Thanks for you input guys! Yes I was thinking about have it on the outside and isolate it. If its onlt hala degree differance from the middle it sounds ok. Would be interesting to test thus during next fermentation. Mabe som cirkulation during fermentation would be nice. Ger a more even temperature.
 
Thanks for you input guys! Yes I was thinking about have it on the outside and isolate it. If its onlt hala degree differance from the middle it sounds ok. Would be interesting to test thus during next fermentation. Mabe som cirkulation during fermentation would be nice. Ger a more even temperature.

Don't worry, the yeast will give you plenty of circulation.:rockin:

[ame]https://www.youtube.com/watch?v=xm33934qM4E[/ame]
 
I have my probe taped to the outside of my carboy. During peak fermentation the krausen sometimes will be 5 degrees higher but the wort directly under the krausen is within a degree or two of my set fermentation temps.
The biggest problem I have is the 3 degree temp swing from when my temp controller (A419) turns on to when it shuts off. I've tried changing the settings but nothing seems to work.
 
I use a thermowell, and the temperature inside the fermenter (which is fermenting vigorously) is currently at 68 degrees, which is 10 degrees above ambient temperature.

During active fermentation the temperature can increase dramatically due to the exothermic reaction of the yeast consuming sugar and swimming around wildly.
I have measured the surface of my fermentor with a pyrometer, and it always shows lower temps than the actual core of the beer.

With my Johnson A419, I always stay within 2 degrees of my set point - currently 66-68.

I wouldn't control the tempeatures any other way than direct contact with the beer.

My 2 cents.

Brew on!:)
 
I also have my probe taped to the side of the carboy. However, I then have a piece of insulation taped over the probe as well. This should insulate the probe from ambient, making it a little more true to what the beer temp really is on the other side of the wall.
 
I have never really logged the temperature of the fermenting beer inside the fermenter before. And it really surprized me how much higher it was during high krausen. Almost 5 degrees celcius.
I use to adjust the temp in fridge to right fermenting temp. But now I understan that I have to get an diptube to get the fridge to keep the beer at right remperature.

I know many of you are doing this. Have you ever logged the beer temperature during the yeast most active period? Do you manage to keep it in the right temp during this time of fermentation? Or does it matter if it gets a bit high?
My beer taste very good, but maybe they could be even better:)

On my ss buckets I have a dual temp controller: chilling loop kicks on when it goes over a certain point and heat pad turns on when it gets too cold. I use an inkbird right now on glass carboys hooked to a heat wrap and don't worry about excessive heat it gets down to 30 f outside but the carboys are in a shed.
 
FVillaToro thanks for the reply. Where is your thermowell at? Inthe middle of fermenter or on the side?
RM-MN yes sure I did not think of that. It surely makes a circulation when it's fermenting wildly[emoji4]
 
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