High Ambient Temperature for 6 - 8 Hours

[BeerANDGin]

Hello,

After spending many months on researching the technicalities of brewing at home, I have finally made time to start brewing in earnest in the past few weeks.

I brewed for the first time 2 weeks ago and have a batch of IPA fermenting nicely in a cool cupboard under the stairs between 16 - 18 degrees C.

I brewed up a batch of Milk Stout on Friday, but unfortunately I can't fit another FV into the cupboard.

The coolest alternative spot I have in the house has been sitting at around 21 - 22 degrees C, however the weather in the UK has warmed up significantly in the past two days (for the UK!) and the ambient temperature around the FV hit 24.6 degrees C yesterday evening.

I have now used the various methods I've read on many threads to cool the ambient temperature back to 21 - 22 degrees C (wet towels, ice bottles and fan).

My question is, will sitting at this higher temperature for 6 - 8 hours so close to the start of fermentation (i.e. within the first 48 hours) have had any significant detrimental effect on the finished beer? I have read that the first 48 - 72 hours is most critical from a temperature perspective and also that these higher temperatures risk the introduction of undesirable flavours/alcohols being produced by the yeast.

I'm using US-05 and understand that it will still perform up to 24 degrees C, however I also realise that the internal temperature of the wort can be several degrees higher than this. Having brought the temperature back down relatively quickly, will this limit the impact? How quickly can the yeast produce enough volume of these flavours/compounds for it to have a noticeable effect on the beer?

(Sorry that was several questions!)

Thanks in advance for any advice you can give.

Les

 

[HBC]

Move the IPA since you are though primary...or.....
You will be fine for the first 12 hours with the stout in a warmer spot......actually, it can act as a bit of a yeast starter for you with the extra few degrees!! After that period though, get her to your goal temp...as those esters will start to show their tasty faces. Same thing at the end of ferment...you can put it back to warm. We do this in our brewery as a diacetly rest....be sure you are well over 50% through ferment though.

 

[BeerANDGin]

Thanks for the quick response HBC.

Have moved the stout to the cupboard and the IPA to the kitchen. Fingers crossed!

Les

 

[BeerANDGin]

A quick update on this brew.

As mentioned above, I moved the FV to a cooler spot in the house and it's been sitting there for the past two weeks.

Took a sample today and tasting really promising with a strong hit of coffee coming from the dark malts and there don't appear to be any strong unwanted esters or fusel alcohol flavours!

The specific gravity is still a little higher than I'd like at 1.030 (OG 1.062). The temperature range over the past two weeks has averaged around 16C-17C, but has been as low as 14C and as high as 21C at times.

I've now moved the FV back into the kitchen (where the average temperature is 19C-20C at the moment) to give the yeast a more stable and slightly warmer environment to finish their job.

I've also just taken delivery of a Cool Brewing Insulated Fermentation Bag to allow me to cool the brew if temperatures were to unexpectedly increase over the next week or so.

Really looking forward to trying this one once racked and conditioned!