Okay, time to stir the hornet's nest...
I see folks on here suggesting that "Oh, US-05 should be fine up into the mid-70's, no problem... It's a very tolerant yeast."
Sorry guys, that's not true. Yes, it'll ferment up there. Yes, a lot of yeasts will ferment up there without turning out terrible beer. But if you want commercial quality beer, you need temp control. There's no other way around it.
It's simple. You ask a brewer who has temp control what his top three brewing processes leading to good beer are, and I guarantee temp control will be in the top three
. It'll often be #1 on the list.
As brewers, we're all proud of the input we have into the process. We ogle over brewporn; beautiful single-tier HERMS setups with total automation. We obsess over mash temp, and boiloff rate, and every little bit of brew-day minutiae.
But you know what? You can screw up most
of that and still have a pretty damn tasty beer if you keep your yeast cool and happy (I know, I've done it). And you can do everything else perfectly on brew-day, but if screw up your yeast, your beer will be sub-par.
Last year I did an experiment with another brewer. On my system, we brewed 15 gallons of DIPA, while I can only ferment 10. So I drew off 5 gallons into his carboy and put the rest in my fermenter. *Everything* about the batches, i.e. recipe, water, process, mash, aeration, etc were identical up until the point yeast (US-05) was pitched. Both were pitched at 64 degrees. Then I temp-controlled my beer, and he took his home to ferment w/o control. Mine fermented at 64 degrees, with a controlled rise to 72 at the very tail end of ferment to finish it off. His climbed up for about a day or so to the 76-78 degree range in the early active fermentation stages before subsiding and coming back down naturally.
We submitted both to a homebrew club meeting for evaluation, including a couple members who are BJCP judges. The results were clear. The temp controlled beer had comments like "good malt and hop balance", "clean crisp bitterness", "great mouthfeel", "great hop flavor". The un-controlled beer was still decent, but with some comments like "very strong grapefruit flavor", "not well balanced", "slightly solventy, little medicinal in the finish", "finish leaves something to be desired".
The temp-controlled beer got judge scores of 40/39/36. The non-controlled (same judges/same order) got scores of 29/32/25. So the scoring ranged from 7 to 11 points difference between temp-control and no control.
So what's the takeaway?
A beer in the 40/39/36 range will commonly medal in competition. A beer in the 29/32/25 range will not. The temp-controlled beer was a very nice
beer. The non-controlled beer wasn't *bad*, but it wasn't good enough to stand alongside a commercial DIPA.
All the brewday factors were identical, but we were left with two very
different beers. If you want your beer to score like the first one, you absolutely need
fermentation temp control.