The best place to get fermentation temperature information is from the yeast manufacturer's website. For example, when I use Wyeast's Dennys Favorite 50, here's the info I look up (
Wyeast Laboratories. Denny's Favorite 50 1450)
YEAST STRAIN: 1450 | Denny's Favorite 50
Back to Yeast Strain List
This terrific all-round yeast can be used for almost any beer style, and is a mainstay of one of our local homebrewers, Mr. Denny Conn. It is unique in that it produces a big mouthfeel and accentuates the malt, caramel, or fruit character of a beer without being sweet or under-attenuated..
Origin:
Flocculation: Low
Attenuation: 74-76%
Temperature Range: 60-70F 15-21C
Alcohol Tolerance: ABV 10%
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Generally, even within that temperature range, I make some decisions about fermentation temperature on my own. I almost always ferment at the low range of each yeast strain's range, unless my personal experience tells me that I should do otherwise. In this case, I use Denny's yeast at about 62-64 degrees and like the results.