Fermentation Problem

[GF21]

Hi all
I have done a St Peters IPA and had an issue thats never happened before . I knocked up the extract and added the hop sachet , then pitched the yeast at 19c . I put the bucket in my cupboard which is at 18/19c constantly .
You can imagine how i felt when i checked it the other morning and it was at 27c , yet the cupboard temp was 19c , how can this happen . It has taken itself back down to 20c (3rd day ) and is still fermenting steadily , my main worry is has it spoilt/ruined the brew , and also how this happened in the first place . Any help will be appreciated folks

 

[Awfers]

At homebrew volumes, yeast will generate some heat as it ferments, normally only a degree or two. I've never heard of it adding 7°C. Are you sure your thermometer was correct? What sort of thermometer are you using?

 

[GF21]

Hi and thanks for the reply , yes , I have 2 stick on thermometers on the bin , and 1 in the cupboard , I also put the nippers thermometer in there for comparison and they all showed the temps i said , I know its wierd , baffled me also , more concerned about the brew tbh

 

[Awfers]

That indeed is odd. The only thing you can do it let it ferment out and bottle it!

 

[Awfers]

Just out of curiosity, what yeast did you pitch?

Some additional research shows that says a fermenter can raise in temp from 5°C to 8°C during active fermentation: Controlling Fermentation Temperature - Brew Your Own

Personally, I've never seen that big of a swing, but my fermenters tend to be taller and thinner than the bucket style.

 

[Obadiah Boondoggle]

Something similar happened to me a few brews ago

Made no difference to the finished product

Just relax and enjoy it

 

[foxy]

You will always see a difference in temperature during fermentation, even from the outside of the fermenter to the core can be 1-2 C. It can be even higher ambient temperature dependent especially at the start.
I look for 16 to 17 C fermenting room temperature, which means I am fermenting around 19-20 C, spring is the worst time for my fermentations can be 35 C one day and 15 C the next.

 

[BridgeBrew]

I've had a razorback go up to 24, in my brewfridge that's set to 19.5 on the STC. It was a very vigarous fermentation, had to fit a blow off tube. It settled back down after a week, and it made no difference to the finished beer. I normally get an increase of about 2 degrees to about 22 on every brew.

 

[foxy]

I checked my Brown Ale this morning, yeast pitched yesterday arvo, first time using Newcastle liquid yeast from Bluestone. Temperature also is yeast dependent, some yeast create more exothermic activity than others. 17.5 C was the ambient temperature in my fermenting room, 21 C was the external temperature of the fermenter so I can hazard a guess of 1-2 C higher at the core. It does settle down to a lower temperature after 18 -24 hours so nothing to be concerned about.