26C too high?

[rhumbunctious]

Hi folks,

I just made my first ever batch two days ago, a Coopers English Bitter, made with 500g LME and 500g dextrose plus the kit yeast, and it's fermenting nicely, though where I have my fermenter, the strip thermometer is showing a steady 25-26C.

Temp was 24C when yeast was pitched, then the fermenter was put into a cupboard out of the "toddler zone" (my 2 year old is facinated with the airlock ;-)

The temp is very stable, with no change at all over the last two days, but I'm worried that perhaps 26C is a bit too high. The problem is I don't really have anywhere else to keep the fermenter where the temp would be any more suitable.

Should I be worried about 26C? What affects might it have on the end result?

FWIW, I plan to leave the brew in the primary for 2 - 3 weeks before bottling.

 

[snowveil]

Coopers yeast strains are pretty tolerant to higher temperatures, but even still at that high of a temperature you're definitely going to be getting some heavy ester production, and possibly fusel alcohols and diacetyl. (banana, bubblegum, harsh solvent, and/or butter flavors). It will still be drinkable, so it's definitely not a lost cause

If you don't have any room in the house that you can get the temperature down, try making a swamp cooler (like many of us do). Basically fill a large bucket with water, put your fermenter in it, drape a t-shirt over the fermenter to wick up the water, and swap out frozen water bottles as needed. This can bring the temperature down quite a few degrees.

Try to keep the vigorous fermentation in check at around 21C or lower.

Good luck and welcome to the hobby

 

[rhumbunctious]

I tossed a cold wet towel around the fermenter and have gotten it down to 24C. I can go out to buy a barrel to cool it further, though I'm wondering whether the damage is already done, with the first two full days of fermentation at 26C and whether, at least for this batch, it wouldn't make any difference bringing it down to 20C for the remainder of the primary fermentation.

Or is there still a chance to "save" the batch from too many off flavors by cooling it from now onwards?

 

[david_42]

Much of the damage, such as it might be, is done; however, a long sit before bottling will clean some of the esters up. Won't do anything for a hot alcohol taste though. That's due to fusel alcohols and once you have them, they don't go away. On the other hand, if you don't have this taste, it probably won't develop now that you've cooled it off.

 

[lurker18]

Agree that any damage is probably already done. The higher temps will get the yeast more active and ferment faster, so in two days, 90% of the fermentation has already happened. Cooling it now probably won't hurt, but time would be your best friend now. Let it sit in the fermentor longer, age in the bottle a little longer, and hopefully the time will clean things up for you.