Fluctuating Fermentation Temp

[cladinshadows]

I brewed two batches last weekend and both are bubbling away (very) happily...but, it's been very warm for the past 24 hours and even my wet towels and fan couldn't keep the carboys below about 72F. I finally set up my coolers with ice water to get them cooled off tonight after about 24 hours of warm temps...

If the first 24 hours of fermentation were very warm, am I doomed to diacetyl and ridiculous esters?

I'm planning to just keep them cool for the week and eventually warm back up toward the end of two weeks, but in your experience, is the damage already done?

 

[Grinder12000]

Doomed? no. It's just something to be concerned over and learn from. I've brewed "hot" beer and it came out fine. however I believe it could have been better . . who knows.

You should be fine. I would let it rest a while once it's finished.

 

[Dwain]

I fermented at room temp for years. Made some great tasting brews. I'm sure they would have been better had they been fermented at the proper temp. but we drank them. Like Grinder said, just learn from it and figure out how you will prevent it from happening again. In all honesty though, I've never made a beer that I didn't enjoy. Some more than others but, IMO, they were making beer long before they could control the temps and I really wouldn't worry about it. Luck - Dwain

 

[bruin_ale]

Depends on the yeast, but 72 isn't that bad. There were times when I didn't have a fermentation fridge that I was fermenting closer to (and sometimes above) 80. The temp on a hot summer day in my garage would get over 80 and a vigorous ferment would push it higher still. I never noticed diacetyl, but in some of those first beers I had some unpleasant esthers (namely banana-like flavors - not a great flavor in a pale ale).

 

[cladinshadows]

My first 24 hours of fermentation were at the high 72-74 range, and then I was able to cool it down to more like 64-68... Would it be a good idea to let it get back up to 72-74 now that fermentation is basically done and do a sort of diacetyl rest to help the yeasties clean up a bit??

 

[cladinshadows]

For anyone who is interested, one of these beers used S-04, the other S-05. The S-04 beer turned out great, and the S-05 had some flavors that I would attribute to hot fermentation temps (unpleasant bitter off-flavor).