Author Topic: Controlled ferment to ambient  (Read 476 times)

Offline gleece

  • 1st Kit
  • *
  • Posts: 11
Controlled ferment to ambient
« on: September 23, 2018, 10:27:54 PM »
I now have a dedicated fermentation chest freezer that is controlled with a Johnson controller. Unfortunately I can only fit one fermenter at a time. I am wanting to brew 3 beers fairly soon. Is there a good time to remove my fermenter from about 63 degrees to an ambient basement storage room temperature of 68 degrees? Will that cause any unwanted off flavors or other problems?

Online Robert

  • Official Poobah of No Life.
  • *
  • Posts: 3756
Re: Controlled ferment to ambient
« Reply #1 on: September 23, 2018, 10:52:34 PM »
If you are at least two-thirds of the way to expected final gravity, the flavor profile dependent on your fermentation temperature has been established.  At that point, you can allow the beer to free rise to ambient temperature,  and this will ensure that the yeast stays active, attenuates fully, and effectively reduces diacetyl and other undesirable fermentation products.  Many brewers include such a temperature increase in their fermentation programs (often called a "diacetyl rest," but sulfur compounds and other things are also reduced.)
Rob Stein
Akron, Ohio

I'd rather have questions I can't answer than answers I can't question.

Offline dmtaylor

  • Official Poobah of No Life.
  • *
  • Posts: 3660
    • Manty Malters - Meet the Malters! - Dave Taylor
Re: Controlled ferment to ambient
« Reply #2 on: September 24, 2018, 12:33:49 AM »
If you are at least two-thirds of the way to expected final gravity, the flavor profile dependent on your fermentation temperature has been established.  At that point, you can allow the beer to free rise to ambient temperature,  and this will ensure that the yeast stays active, attenuates fully, and effectively reduces diacetyl and other undesirable fermentation products.  Many brewers include such a temperature increase in their fermentation programs (often called a "diacetyl rest," but sulfur compounds and other things are also reduced.)

+1.  Second half of fermentation or so is just fine to warm things up.  I always do.
Dave

The world will become a much more pleasant place to live when each and every one of us realizes that we are all idiots.

Offline charlie

  • Assistant Brewer
  • ***
  • Posts: 144
Re: Controlled ferment to ambient
« Reply #3 on: October 02, 2018, 02:22:06 AM »
I leave my ales in the FC for 7 to 8 days, and then bring them in the house to finish at room temp. It works, and the yeast doesn't throw any off flavors in the final stages of fermentation.

Charlie
Yes officer, I know that I smell like beer. I'm not drinking it, I'm wearing it!

Online Robert

  • Official Poobah of No Life.
  • *
  • Posts: 3756
Re: Controlled ferment to ambient
« Reply #4 on: October 02, 2018, 02:34:48 PM »
You really should go by gravity readings and not a predetermined time, though.  Ale fermentations usually go to completion in 3 days, but possibly as little as 24-36 hours, lagers in 7 days.  If you want to do a "diacetyl rest" by allowing free rise at a certain point in the active fermentation,  it's easy to miss your opportunity.   Incorporating the temperature rise in the fermentation program will "clean up" a beer (that is, achieve full flavor maturation) by the time it reaches FG or within a day or two thereafter.  If you warm it up after it's complete, as long as there's live yeast present, it will eventually mature, but can take weeks.  Ultimately,  you find a system that works practically for you.  If you regularly use the same yeast under the same conditions, you may learn to approximate timing.  But only gravity will tell you what is really happening.
Rob Stein
Akron, Ohio

I'd rather have questions I can't answer than answers I can't question.

Offline ynotbrusum

  • Official Poobah of No Life.
  • *
  • Posts: 3205
Re: Controlled ferment to ambient
« Reply #5 on: October 03, 2018, 01:21:22 AM »
You really should go by gravity readings and not a predetermined time, though.  Ale fermentations usually go to completion in 3 days, but possibly as little as 24-36 hours, lagers in 7 days.  If you want to do a "diacetyl rest" by allowing free rise at a certain point in the active fermentation,  it's easy to miss your opportunity.   Incorporating the temperature rise in the fermentation program will "clean up" a beer (that is, achieve full flavor maturation) by the time it reaches FG or within a day or two thereafter.  If you warm it up after it's complete, as long as there's live yeast present, it will eventually mature, but can take weeks.  Ultimately,  you find a system that works practically for you.  If you regularly use the same yeast under the same conditions, you may learn to approximate timing.  But only gravity will tell you what is really happening.

And knowing final attenuation requires either FFT or knowledge of the yeast in the particular recipe.  ;)
Hodge Garage Brewing: "Brew with a glad heart!"