Author Topic: Fermentation temp changing by + \ - 5 degrees  (Read 3774 times)

Offline JPSwanson91

  • BeerSmith Apprentice Brewer
  • **
  • Posts: 6
  • BeerSmith 2 Rocks!
Fermentation temp changing by + \ - 5 degrees
« on: August 25, 2014, 09:57:08 PM »
12 hours into primary fermenting a Blonde Ale pitched at 65 degrees, the fermentation temp sky rocketed all the way to 77 degrees ( stored in 70 degree basement).  I went out and bought a tub, filled with water and dropped in two milk jugs filled with frozen water.  The temp dropped all the way down to 64.  I have been changing out frozen water bottles for a week now but temp keeps swinging up and down from 64 -70 degrees.  Bubbling was not as wild as it was for my IPA and slowed to almost nothing after just three days.

#1.  Should I pitch more yeast?  Will that fix any off flavors?

#2.  What does the frequent temp changes do to my beer?

Offline brewfun

  • BeerSmith Grandmaster Brewer
  • *****
  • Posts: 2304
  • Malt dust is just alcohol's glitter
Re: Fermentation temp changing by + \ - 5 degrees
« Reply #1 on: August 26, 2014, 06:16:59 AM »
How are you measuring the fermentation temperature?

Bubbling was not as wild as it was for my IPA and slowed to almost nothing after just three days.

Different recipes are going to have different fermentation characteristics. Higher OG recippes are usually going to have more vigor.  A 3 day primary is ok. Most of my primaries are 4 to 5 days at normal temperatures. Warmer fermentations tend to finish faster.

Quote
#1.  Should I pitch more yeast?  Will that fix any off flavors?

No and usually no. Usually esters and a little fusel alcohol is the only consequence of hot fermentation.

Quote
#2.  What does the frequent temp changes do to my beer?

 Fusels often oxidize into esters. Unless you pitched a strain that's prone to phenols or have a sanitation issue, the beer should otherwise be ok.

Beer Appreciation is the space between pints.

Offline JPSwanson91

  • BeerSmith Apprentice Brewer
  • **
  • Posts: 6
  • BeerSmith 2 Rocks!
Re: Fermentation temp changing by + \ - 5 degrees
« Reply #2 on: August 26, 2014, 04:34:32 PM »
I am measuring the temp with a temperature strip on the outside of my bucket.  It sounds like everything is ok based on what you said, except for some unwanted esters that may bring out some off flavors.
I checked the gravity this morning and it was already at 1.016 which is close to expected FG.  I'll measure again in three days and rack to secondary if it looks like it is done.

Going forward, I will need to get some sort of temperature controlled fridge.  Trying to keep a consistent temp in the Midwest in summer is just too difficult.  I can see why some people brew in spring and fall only.

Thanks for the help...

Offline Maine Homebrewer

  • BeerSmith Grandmaster Brewer
  • *****
  • Posts: 1371
Re: Fermentation temp changing by + \ - 5 degrees
« Reply #3 on: August 26, 2014, 06:31:37 PM »
Quote
I can see why some people brew in spring and fall only.

Or brew ales in the spring and fall, and maintain a fifty degree basement in the winter for lager.  ;)
"To alcohol! The cause of - and solution to - all of life's problems!" -Homer Simpson