# Ale fermentation temp



## buntung483 (13/2/13)

Hi
I have an extract IPA that I have started ferment with us05. I'm using temp control for first time at 17.5c. So far looks like nice activity. 

I was hoping someone could tell me what can happen at different temps. I know high temp causes off flavored but what will my temp produce compared to the same beer at say 22c

Thanks for help


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## slash22000 (13/2/13)

I'd be interested to see if anybody has done a "degree by degree" comparison, but I've never seen one. Basically as you said, the higher the temperature the more off-flavours the yeast may/will produce. To quote:

_"Fermenting at higher temperatures produces unwanted flavors in beer due to the increased metabolic activity. Off flavors such as fruity esters and solventy higher order alcohols, are generated. Acetaldehyde (green apple), in particular, is produced at a much higher rate during increased fermentation temperatures and is one of the most common faults in homebrewed beer. _

_Fermenting below a yeast’s range will decrease these metabolites, but you also risk a sluggish fermentation, poor start to fermentation, and possible attenuation issues. The first generation of yeast is also susceptible to high fermentation temperatures as further pitches will suffer in quality."_ - http://sciencebrewer.com/tag/fermentation-temperature-experiment/

17.5ºC is actually slightly lower than recommended for that yeast. 18ºC is perfect. 0.5ºC won't hurt anything, just pointing it out.


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## buntung483 (13/2/13)

Hmm maybe I'll bump it up a degree. Only been goin a couple days. I will bump it up towards the end for diactyl rest also . Thanks for the reply. I will try to find some more info


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## yum beer (13/2/13)

Try and avoid higher end of the temp range. The yeast will work but I have always found that the lower end is much cleaner.
I have often brewed with ale yeast as low as 15c for great results.


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## yum beer (13/2/13)

buntung483 said:


> Hmm maybe I'll bump it up a degree. Only been goin a couple days. I will bump it up towards the end for diactyl rest also . Thanks for the reply. I will try to find some more info


You dont need a d rest with ale yeasts, they dont throw diacetyl like lager yeasts.


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## Nick JD (13/2/13)

I just did a US05 ferment at Gold Coast February ambient during a 4 day powercut. Probably averaged about 30C.

It's fruity. Totally drinkable.


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## browndog (13/2/13)

You can ferment at 20C with this yeast with no problems what so ever.


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## Charst (13/2/13)

yum beer said:


> You dont need a d rest with ale yeasts, they dont throw diacetyl like lager yeasts.


Yeah and that is why you never taste Diacetyl in English Ales :blink:


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## buntung483 (14/2/13)

Thanks for the feed back. Ill keep it fermenting at the 17.5 and let it do its thing. Maybe next time ill try a different temp with the same recipe( as long as it turns out good) see what happens. 

Cheers


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