Author Topic: Fermentation Temp - what is the impact  (Read 859 times)

Offline desi

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Fermentation Temp - what is the impact
« on: April 15, 2016, 11:12:10 AM »
So, I'm new to brewing and I'm brewing a KBS clone (go big or go home right?) and the recipe calls for a primary fermentation temp of 65 degrees F.  My basement is very consistent.  Consistent at 56 degrees F.

what is the impact on the beer of different fermentation temps?

-desi

Offline Slowbrew

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Re: Fermentation Temp - what is the impact
« Reply #1 on: April 15, 2016, 11:31:14 AM »
Your beer ferment at a temp higher than the ambient room temp due to heat produced by the yeast.  I would think you should okay at the temp in your basement.

The major problem I run in to with temp is not being able to get down to the recommended temp.  If the fermentation gets too warm if can produce rather nasty off flavors. 

That being said, you can go too low too and cause the yeast to go dormant or ferment very slowly.  this can give infections the time they need to get a foothold.

Paul
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Offline desi

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Re: Fermentation Temp - what is the impact
« Reply #2 on: April 15, 2016, 11:53:49 AM »
that is interesting info.  the fermentation did talk almost 48 hours to begin and has gone very slowly.  My thoughts on that is that for such a large beer, I probably should have pitched two packets of yeast but I only had one.

Offline brewinhard

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Re: Fermentation Temp - what is the impact
« Reply #3 on: April 15, 2016, 12:18:23 PM »
At 56F as an ambient temp of the room, you may want to consider putting a t-shirt over the fermenter just to keep a bit of heat in so you can reach 65F or so as an actual fermentation temp.  Do you have a fermentation thermometer sticker (at least) on your fermenter so you can get somewhat of a range of temp you beer is fermenting at?

Offline HoosierBrew

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Re: Fermentation Temp - what is the impact
« Reply #4 on: April 15, 2016, 12:24:02 PM »
+1.  Keep in mind that a beer as big as a KBS type beer will produce maybe twice the fermentation heat as a 1.050 beer. I wouldn't want to pitch at much over 60F for any beer that big. Not totally related to your initial question, but be extra sure to pitch much more yeast than you would for a standard beer and aerate for twice as long to give you good results.
Jon H.

Offline desi

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Re: Fermentation Temp - what is the impact
« Reply #5 on: April 15, 2016, 01:45:03 PM »
Thanks for all the help.  Great info

Offline zwiller

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Re: Fermentation Temp - what is the impact
« Reply #6 on: April 15, 2016, 02:07:06 PM »
Be sure to measure your pitching temp prior to pitching.  You might be surprised how long it takes for 80F wort to get down to 60F ambient...  Just let it cool and acclimate if it's high.  This is typically overnight for me in summer months.  IMO pitch temp is more critical than ferment temp.  I also agree that 56F is just on the cool side and could possibly affect yeast performance.  Hopefully, there is a spot that is just a touch warmer or a way to manipulate ambient temporary.  IE: open a vent/door/leave a light on. 
Sam
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Offline Pinski

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Re: Fermentation Temp - what is the impact
« Reply #7 on: April 15, 2016, 03:30:10 PM »
So, I'm new to brewing and I'm brewing a KBS clone ...

Well, confidence is a key ingredient when you're starting out. I like your style. You've got some good tips here to point you in the right direction. Good luck!
Steve Carper
Green Dragon Brew Crew
Clubs: Oregon Brew Crew & Strange Brew
BJCP Certified

Offline desi

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Re: Fermentation Temp - what is the impact
« Reply #8 on: April 15, 2016, 05:21:23 PM »
Thanks everyone.  As usual, homebrew nation does not disappoint.

Offline euge

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Re: Fermentation Temp - what is the impact
« Reply #9 on: April 15, 2016, 05:24:22 PM »
It might not be a bad idea to use a tub of water to drop the temp quicker instead of ambient air.



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Offline TeeDubb

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Re: Fermentation Temp - what is the impact
« Reply #10 on: April 15, 2016, 07:50:44 PM »
For me, fermentation temperature control (following a specific profile) was the single largest quality improvement to my beer making over the last year. Of course, some styles and yeast strains are more sensitive to temp changes, others are more tolerant. I've been making mostly ales and the occasional stout lately. Pitching the right amount of yeast at the initial target temp. was also significant as it seemed to get the fermentation active within 6-12 hrs after pitching, complete a lot faster, with much cleaner flavors.

That said, there is a lot you can do with little investment. Using a water bath around the fermenter that is held at desired temperature works very well.  Add ice (or warm water or use a cheap aquarium heater in the bath if you're fermenting in a cold basement) as needed during the most vigorous stage of fermentation (first 2-3 days or so). In the early days, I also used a wet towel and a small PC fan to cool the fermenter.  Works well, but you need to monitor on a daily basis.

Good luck!