Temperature and Fermentation

Budista · 04-05-2010, 10:01 PM

Hey all,

First time brewer here. I did read the forums, but couldn't really get a solid 'yes' or 'no' answer to my question, so I figured I'd just add another thread to the many already on the topic.

I've started my very first brew yesterday and kept a close eye on sanitizing everything and following the directions very carefully.

However, when I left for work this morning, the primary fermenter was at 71 degrees and bubbling nicely. When I got home, though, it was at 80 and bubbling VERY aggressively (I could actually hear a foaming sound when I opened the top of the pail). I immediately put it in a water bath with a couple frozen bottles (thank you, internet) but am curious whether 8 hours at 80 degrees is really going to affect the flavor of the beer.

For what it's worth, it's a very simple kit beer and took next to no work on my part other than the sanitization. Fermentation is definitely started, but I don't know if the beer (just a 'Draft' style) is going to be adversely affected by 8 or 9 hours at a high temperature. I'll monitor it closely with the water bath and hopefully can keep it between the 65-75 degrees the instructions dictated.

Thanks for any opinions! This is already fun and I've barely started.

- Budista

**pompeiisneaks** · 04-05-2010, 10:11 PM

The short answer is yes, definitely.

The Longer answer is that yeast fermenting at that high of a temperature have a higher chance to be stressed and mutate causing off flavors. The good thing is that getting it down gives the yeast a chance to relax and start working normally. you may find odd flavors initially, but give the yeast time to clean up after themselves. Leave in primary 3-4 weeks to let the yeast clean up all those off flavors. Then let it age longer after that in bottles or keg/whatnot and do periodic taste tests. It will likely end up fine after time. It may even, if you're lucky, not have much of an off flavor that may just clean up fine in the 3 to 4 weeks.

Budista · 04-05-2010, 10:19 PM

That was sort of what I had feared, but from everything I've read, age will improve most of the issues I'll come across.

One thing that seems to be inconsistent across the board is the discrepancy between primary and secondary fermentation.

Some of what I read has primary occurring in a large bucket, like a brewing 'pail', with the secondary continuing (after about a week or so in the primary) in a carboy. Following the normal 3-4 weeks in the carboy, it goes into bottles for a couple weeks before it's drinkable.

Am I reading wrong, or is this the procession that should occur?

- Budista

mightynintendo · 04-05-2010, 10:19 PM

Honestly it's probably fine, though you MAY notice some not-quite-right flavors at the end of your fermentation schedule. Experience lends me to think that if these flavors/odors are present, they will dissipate with age. I think you did the right thing though with the water bath. If not using a water bath, during the first few days of fermentation the ambient air should be about 10 degF cooler than your target temp. That's a general suggestion not an exact science. Try to keep it below 70 and above 65 as much as you can from here out and I think it will turn out to be quite good. That too is just my advice without knowing what yeast you're using.

**pompeiisneaks** · 04-05-2010, 10:32 PM

Generally I just use a primary only, I'll let it sit for 3-5 weeks depending, and the yeast do their work. I then keg/bottle and usually in keg I start drinking as soon as I can get good carbonation. I've had a few ferment a bit high, 74 to 76 range and they came out find after a bit more aging.