Topics Topics Help/Instructions Help Edit Profile Profile Member List Register  
Search Last 1 | 3 | 7 Days Search Search Tree View Tree View  

Visit The Brewery's sponsor!
Brews & Views Bulletin Board Service * Brews and Views Archive 2003 * April 15, 2003 * Fermenting creating heat.. < Previous Next >

  Thread Last Poster Posts Pages Last Post
  Start New Thread        

Author Message
 

Walt Fischer (24.221.196.114)
Posted on Sunday, March 30, 2003 - 09:28 pm:   Edit Post Delete Post View Post/Check IP    Ban Poster IP (Moderator/Admin only)

Sooo what type of temp raise occurs from the fermenting process? How exactly does fermenting raise the temp?

Bill? :)

Walt
----
 

Fredrik (213.114.44.196)
Posted on Sunday, March 30, 2003 - 10:53 pm:   Edit Post Delete Post View Post/Check IP    Ban Poster IP (Moderator/Admin only)

I don't know the details but as far as I understood (beware that I am new to brewing myself so don't take my word for it) most of the heat beeing released during fermentation is from oxidation of glyceraldehyde-3-phosphate, beeing a intermediate in glycolysis. Glycolysis is the sub process chain where glucose is converted to puryvic acid. Next (alcoholic fermentation) puruvic acid is converted into etanol, but I don't think this releases any significant heat.

I do not have any experience regarding temperature but I think I've seen other people report temperature inside the bucket beeing something like 2-3 degrees higher than the ambient temperature? Otherwise I trust you could calculate it from the specific heat release during glycolysis.

http://www.sp.uconn.edu/~bi107vc/fa02/terry/metabolism.html

is an link I found that I like

/Fredrik
 

don price (65.32.41.146)
Posted on Monday, March 31, 2003 - 12:42 am:   Edit Post Delete Post View Post/Check IP    Ban Poster IP (Moderator/Admin only)

Skipping the chemistry and straight to practical thermodynamics....my memeory and relatively limited personal experience indicates a temperature rise of 5-10 F above ambient temperatures during peak fermentation (first 24-72 hours?) in 6 gallon carboys. Please note that high gravity brews that start relatively warm (say 1.080 imperial stout on a WY1056/WLP001 yeast cake at 75 F - not a good idea) will give a much higher temperature rise than a lower gravity beer started with less yeast at a lower temperature. Start low and slow enough and you won't get much temp rise, or fermentation, at all. Temperature affects flavor so I won't try to tell you what is right for you.

Don
 

Bretth (12.253.241.217)
Posted on Monday, March 31, 2003 - 02:00 am:   Edit Post Delete Post View Post/Check IP    Ban Poster IP (Moderator/Admin only)

You kill me, Fred!
 

Brandon Dachel (208.44.235.190)
Posted on Monday, March 31, 2003 - 01:30 pm:   Edit Post Delete Post View Post/Check IP    Ban Poster IP (Moderator/Admin only)

> How exactly does fermenting raise the temp?

It's an exothermic reaction. :)
 

Bill Pierce (208.57.122.28)
Posted on Monday, March 31, 2003 - 03:59 pm:   Edit Post Delete Post View Post/Check IP    Ban Poster IP (Moderator/Admin only)

Exactly. Most organic reactions are exothermic, that is, they release energy in the form of heat. Think of the reactions in the body when we metabolize food.

Add Your Message Here
Posting is currently disabled in this topic. Contact your discussion moderator for more information.