The Great Bottle Opener Giveaway

Home Brew Forums > Home Brewing Beer > Fermentation & Yeast > Fermentation produces heat??? Or not!

Reply
 
LinkBack Thread Tools
Old 05-10-2013, 02:58 PM   #1
lyonshead
Feedback Score: 0 reviews
Recipes 
 
Join Date: Mar 2013
Posts: 51
Liked 3 Times on 3 Posts

Default Fermentation produces heat??? Or not!

I recently purchased a Taylor thermometer with a submergible probe, allowing me to monitor my actual fermentation temp for the first time. The previous method was to tape an insulated a419 probe to the side and just trust that I was close to the real temp.

My latest setup had the Taylor submerged and the a419 stuck to the side while controlling a fermwrap. Just so happens that the time of year has my basement at a consistent 64*. My target temp was also 64 so I was worried that the temp increase caused from fermentation would have me well over my temp and the fermwrap would really be pointless, as I would need to be cooling the wort, not heating it. Not so my friends!

As it turns out my beer has not moved a single degree the entire time. The Taylor measures degrees in .1 increments. I have seen fluctuations from 64.2 to 64.8 and that is it. The Johnson probe reads 64 on the outside and hasn't kicked on the fermwrap one time. Basically my efforts for temp control are pointless because the current basement temp is perfect!

My point in all of this, however, is what's the deal with the idea that fermentation increases the temp of your wort. That very clearly did not happen here. Is this a myth to drop in the bucket with all the others??

__________________
lyonshead is offline
 
Reply With Quote Quick reply to this message
Old 05-10-2013, 03:02 PM   #2
hunter_la5
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jul 2012
Location: New Braunfels, TX
Posts: 1,578
Liked 466 Times on 308 Posts
Likes Given: 1268

Default

Did you check to see if the wort was actually fermenting?

All kidding aside, if your measurements are accurate this is indeed interesting. I've always been under the impression that internal fermentation temps could exceed ambient temps by up to 10 degrees - a far cry from what you're seeing.

What kind of beer and yeast? Just curious.

__________________
My coffin keezer build.
Primary: 1. Jamil's Cowboy Alt
On Tap:
1. Brazos Bock,
2. Yooper's Fizzy Yellow Beer
3. KingBrianI's Common Room ESB
hunter_la5 is offline
 
Reply With Quote Quick reply to this message
Old 05-10-2013, 03:08 PM   #3
ajdelange
Senior Member
HBT_SUPPORTER.png
Feedback Score: 0 reviews
Recipes 
 
Join Date: Aug 2010
Location: McLean/Ogden, Virginia/Quebec
Posts: 5,585
Liked 516 Times on 423 Posts
Likes Given: 14

Default

Yes, fermentation produces heat. You can look in a brewing text and find out just how much. It is not enough to cause a temperature rise unless the surface to volume ratio is small (large volumes). This is why it is not noticeable at home brew scale.

__________________
ajdelange is online now
 
Reply With Quote Quick reply to this message
Old 05-10-2013, 03:11 PM   #4
lyonshead
Feedback Score: 0 reviews
Recipes 
 
Join Date: Mar 2013
Posts: 51
Liked 3 Times on 3 Posts

Default

Ha absolutely fermenting. Been monitoring very closely.
1.050 pale ale, very straight forward recipe.
US-05 properly rehydrated and pitched into 64 degree wort!

I'm with ya! That's what I've always HEARD and to this point believed!

__________________
lyonshead is offline
 
Reply With Quote Quick reply to this message
Old 05-10-2013, 03:13 PM   #5
RmikeVT
HBT_SUPPORTER.png
Feedback Score: 0 reviews
Recipes 
 
Join Date: Apr 2012
Location: Baltimore, MD
Posts: 597
Liked 72 Times on 62 Posts
Likes Given: 6

Default

I active ferment in a swamp cooler. I did an experiment where I measured the swamp water temp and then the fermentation temp in the middle of the fermentation column. I found the temps to be with in a degree of each other. Concluding that the water in the swamp cooler is very effective at maintaining the internal temp of fermentation.

For my typical US-05/WLP001 Pale Ale fermentation, I like to keep ferm temp around 66-68. I usually start the swamp water (water bath) around 64*, once fermentation gets going into full swing, usually about 24 hours, it raises the entire bath temp up to 66-68 (ambient is 64) and maintains it until fermentation slows down at which point the swamp water drops back down to a little less than ambient. So, my experience says that fermentation definitely generates considerable energy.

Are you measuring ambient temp and wort temp with the same instrument? If not have you calibrated both instruments too each other? I am pretty surprised at your observation.

__________________
RmikeVT is offline
 
Reply With Quote Quick reply to this message
Old 05-10-2013, 03:18 PM   #6
RmikeVT
HBT_SUPPORTER.png
Feedback Score: 0 reviews
Recipes 
 
Join Date: Apr 2012
Location: Baltimore, MD
Posts: 597
Liked 72 Times on 62 Posts
Likes Given: 6

Default

Quote:
Originally Posted by ajdelange View Post
Yes, fermentation produces heat. You can look in a brewing text and find out just how much. It is not enough to cause a temperature rise unless the surface to volume ratio is small (large volumes). This is why it is not noticeable at home brew scale.
Are you talking about actual fermentation temperatures rising? They definitely increase at the homebrew level. Depending on gravity of wort, yeast and ambient temps the internal fermenation temperature can be 5 to 10 degrees above ambient air temps if not controlled.

BYO just did an article on it, recently.
__________________
RmikeVT is offline
 
Reply With Quote Quick reply to this message
Old 05-10-2013, 03:20 PM   #7
lyonshead
Feedback Score: 0 reviews
Recipes 
 
Join Date: Mar 2013
Posts: 51
Liked 3 Times on 3 Posts

Default

I have calibrated both instruments. But even if I hadn't it wouldn't seem to matter. Neither instrument (ambient or wort) has fluctuated. If they were independent of one another, they are still reading steady temps regardless of fermentation. I took a mercury thermometer into the room as well just to double check the air temp... 64 degrees!

I will say that I have not taken a final gravity reading yet. I'm quite curious now though. The fermentation is 7 days in and from my view through the Carboy and exp with this yeast, it was wrapping up last night/this morning. Everything about this ferment appeared standard

__________________
lyonshead is offline
 
Reply With Quote Quick reply to this message
Old 05-10-2013, 03:26 PM   #8
lyonshead
Feedback Score: 0 reviews
Recipes 
 
Join Date: Mar 2013
Posts: 51
Liked 3 Times on 3 Posts

Default

Quote:
Originally Posted by RmikeVT

Are you talking about actual fermentation temperatures rising? They definitely increase at the homebrew level. Depending on gravity of wort, yeast and ambient temps the internal fermenation temperature can be 5 to 10 degrees above ambient air temps if not controlled.

BYO just did an article on it, recently.
I read the same article... That's why I felt compelled to start this thread! I have a tendency to take the word of those more experienced as gold! but my results just don't match what the experts say
__________________
lyonshead is offline
 
Reply With Quote Quick reply to this message
Old 05-10-2013, 04:04 PM   #9
ajdelange
Senior Member
HBT_SUPPORTER.png
Feedback Score: 0 reviews
Recipes 
 
Join Date: Aug 2010
Location: McLean/Ogden, Virginia/Quebec
Posts: 5,585
Liked 516 Times on 423 Posts
Likes Given: 14

Default

As I noted earlier you can look in a brewing text and find out how many joules per second are released by an actively fermenting wort and from there do the math to figure how much rise you will get for a particular wort mass, fermenter geometry and thermal impedance. There will be a rise but for 5 gallons it isn't likely to be much and, of course, most of the rise would be at the core so you'd want to get your probe down into the core to see it.

As for the 'experts' I have seen some amazing things published. I haven't seen this article in particular so can't comment.

__________________
ajdelange is online now
 
Reply With Quote Quick reply to this message
Old 05-10-2013, 04:13 PM   #10
Facinerous
HBT_LIFETIMESUPPORTER.png
Feedback Score: 0 reviews
 
Facinerous's Avatar
Recipes 
 
Join Date: Apr 2013
Posts: 289
Liked 45 Times on 37 Posts
Likes Given: 18

Default

I have to agree with Rmike. Having a temp increase above ambient would directly corrilate with OG, yeast strain, and ambient temp. Since the temp you are fermenting at is at the mid-low range of the yeast your fermentation won't be very vigorous.

I did a stout reciently where I fermented at a farely high temp (70 degrees) and I usea fermentation chamber . Even in the midst of night were the temp outside was 45 or so the fermentation was hot enough to continuously raise the temp of my box kicking on my cooler. Needless to say I was impressed.

__________________

We learn best from our failures, not our successes.

Facinerous is offline
 
Reply With Quote Quick reply to this message
Reply


Quick Reply
Message:
Options
Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Bottling or Kegging - which produces better beer? xmacro Bottling/Kegging 3 10-05-2012 03:35 PM
Bottling or kegging: which produces the better results? MikeFallopian Bottling/Kegging 9 08-26-2011 07:39 AM
Help: Fermentation produces sulfur smell; alternative source of nitrogen? quaternio Mead Forum 9 09-21-2010 09:47 PM
Wheat produces more phenols? ElDuderino Recipes/Ingredients 6 07-09-2009 05:55 PM
Interested in how much heat a fully fermenting primary produces? Medo General Beer Discussion 5 02-04-2009 08:35 PM