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Old 11-22-2008, 11:11 PM   #1
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Apr 2007
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It's been discussed quite a number of times here and some people worry about fermenting "too low."

IMO, fermenting at very low temperatures will offer no ill affect, it will simply make the beer cleaner. it make take longer to ferment and you may have to rouse the yeast again, but the only risk you are running is causing the yeast to go dormant. This doesn't stress them, from my understanding, and simply raising the temp and rousing them will fix the problem.

In my experience, the only thing that "stresses" yeast and causes off flavors is very high fermentations, or rapid temperature fluctuations (inconsistent temps)

In any case, i'd much rather experience a slow or stuck ferment from temps below the recommended range than esters and phenolics from temps above.

What are your thoughts and experience on the matter?
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Old 11-22-2008, 11:13 PM   #2
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I've always been taught that lower is better, for exactly the same reasons you mentioned....cleaner taste, less ester production. less chance of getting a headache from the beer...

I know that the brewmeister of Rogue ferments pacman between 60 and 70 degrees depending on the beer...but says he prefers doing it at 60 degrees...
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Old 11-23-2008, 03:16 AM   #3
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I have found that each yeast has a sweet spot temperature and that it is best to err on the side of colder temperature. I wish new brewers would pay more attention to this and we would have a lot less fermentation problems and "off- flavors" to fix. The other problem is none of the new brewers want to let the beer stay in the primary long enough to finish cleaning up after the main fermentation.

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Old 11-23-2008, 03:50 AM   #4
Jul 2008
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Well, one problem could be a slower starting fermentation could lead a new brewer to infection depending on sanitation practices and the amount of lag time. Agreed though, that warm fermentation is much more costly to a brew than lower if you are good with sanitation.

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Old 11-23-2008, 10:12 AM   #5
Jun 2008
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This season I fermented 3 weizens cold - 15-17*C. They taste very good, but I see strange over-attenuation effect. They get down from 13 to 2 Plato, maybe they yeast mutated somehow in such cold temperatures.
The last batch - roggenbier stays now 3 weeks on primary, it has 2.5 Plato and airlock still bubbling.

I had no problem with lagtime. With proper pitching they start in couple of hours.

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Old 11-23-2008, 03:15 PM   #6
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Apr 2007
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I agree with WBC in that every yeast is different. I know that I really prefer my Cal Ale strains (only used 001 and S-05, never 1056 yet) below 65. But I'm also using these for things were the yeast flavor isn't necessary. I just pitched close to a 4L starter of straight slurry at 57. I'm hoping it will take off - I want to see how low I can get it to work. I've heard as low as 50.

On the other hand, the Saisons I've made where I pitched and fermented right at 80 has a fantastic pepper spice with some subtle background citrus. It attenuated down to 1.010, as well. I pitched this same yeast into a different Saison at 68 and did the ramp up thing. The spice is still there, but it only attenuated to 1.018. So in terms of flavor profile, they are very similar, but it greatly affected attenuation.

I really want to try the Hefe yeast (WY3068) at 62, which is what is recommended by Jamil. Maybe do a side by side with one that low and another around 70 and see how the flavors are affected.

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Old 11-23-2008, 04:08 PM   #7
Oct 2008
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Within the livable range of the yeast (and yes, certainly at the upper and lower limit of its temp range you will select for mutants) The temp will affect the flavor profile. So its really a matter of taste - a estery flowery beer will benefit from a higher temp.

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Old 11-23-2008, 04:13 PM   #8
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Originally Posted by giligson View Post
Within the livable range of the yeast (and yes, certainly at the upper and lower limit of its temp range you will select for mutants) The temp will affect the flavor profile. So its really a matter of taste - a estery flowery beer will benefit from a higher temp.
I agree that it depends on the beer style/yeast. For beers that you don't want much of an ester profile or are using a fairly neutral yeast (think Pale Ales or Notty) cooler is probably better, if longer. O nthe other hand if you want something with more of an ester or yeast flavoring (Belgians/Hefe's) mid to upper could be better to an extent

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Old 11-23-2008, 04:39 PM   #9
Sep 2007
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I agree that fermenting at the lower end avoids a lot of potential problems with stinky off-flavors. Just to offer a slightly different take, I've also heard various brewers (including some well-respected Belgian brewers quoted in "Brew Like A Monk") advocate upping the temperature towards the end of primary fermentation to help dry out the beer. I've used that technique and (anecdotally, at least) it gives very good results. According to Jamil's podcast on big-ass Belgians, the more funkiness you want from your yeast, the earlier in fermentation you'd ramp the temps up. But starting low seems very widely taken as a good idea.
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Old 11-23-2008, 08:26 PM   #10
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Liked 535 Times on 408 Posts I'm thoroughly confused. I moved my two carboys upstairs to a room that is 69 because my 'brew room' in the basement was hovering around 62.....One has a Hoegaarden clone form AHS with Belgian Wit Ale 400 (White labs) that's been in the primary 11 days and the other is a SA Cream Stout clone from AHS with the White Labs English Ale 002 that I brewed yesterday and is already starting to bubble in the blow off... Should I move 'em back downstairs? Or move just the Hoegaarden since I think it finished the major fermentation yesterday?

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