I am trying to figure out how much heat is created by fermentation.
Does anyone know a formula? something i can plug in 11 gallons and 5% and give me BTU's?
Brewing Science and Practice has a chapter on it, but it is $$ book and must pay to even view it online...
just tapping into the vast K-nowledge of the Guild.
Heat of Fermentation
Moderator: Officers
-
twedelc
- Homebrewer
- Posts: 175
- Joined: Tue Jul 11, 2006 12:17 pm
- Location: twedelc@gmail.com
- Contact:
yikes.......i know of no formula. Wow, that would have alot of criteria involved with that. For example, wort fermability, pitch rate, wort temp, aeration. Thats alot of variables that most homebrewers take care of, but dont know the exact figures of any of those. But, i can tell you from experience that a 10-11g batch of a well areated hi fermatable wort thats pitched with cultivated yeast will raise in temp betwen 6-8* at hi krausen. Ive always based my ferments on that.
But i use ferment fridges and use thermowells to monitor core temps of the beer and i pitch most ales at 65-68* and have the fridge keep it there for me....hope this kinda helps.....
But i use ferment fridges and use thermowells to monitor core temps of the beer and i pitch most ales at 65-68* and have the fridge keep it there for me....hope this kinda helps.....
Just call me Andy!
Lupulin Threshold Shift
lupulin threshold shift \lu·pu·lin thresh·old shift\ n
1. When a once extraordinarily hoppy beer now seems pedestrian.
2. The phenomenon a person has when craving more bitterness in beer.
3. The long-term exposure to extremely hoppy beers; if excessive or prolonged, a habitual dependence on hops will occur.
4. When a "Double IPA" just is not enough
Lupulin Threshold Shift
lupulin threshold shift \lu·pu·lin thresh·old shift\ n
1. When a once extraordinarily hoppy beer now seems pedestrian.
2. The phenomenon a person has when craving more bitterness in beer.
3. The long-term exposure to extremely hoppy beers; if excessive or prolonged, a habitual dependence on hops will occur.
4. When a "Double IPA" just is not enough
-
twedelc
- Homebrewer
- Posts: 175
- Joined: Tue Jul 11, 2006 12:17 pm
- Location: twedelc@gmail.com
- Contact:
so i did some searching and then some math and biochem...
I think the contant is 113.25 BTU's per gallon-% alcohol. (alcohol by weight)
one mole of sugar creates 2 moles of alcohol and CO2 and 118 kJ energy.
C6H12O6 → 2C2H5OH + 2CO2 + 2 ATP (Energy Released:118 kJ mol−1)
http://en.wikipedia.org/wiki/Fermentation#Reaction
so if you had 5 gallons of 5% beer, it fermentation would create 2,831 BTU's
if that happens mostly in 2 days, that would be 59 BTU/hr.
the reason i was researching this is to ofset the heat with ice.
specific heat of ice is .5 BTU/lb, water 1 BTU/lb
latent heat of fusion (melting) 144 BTU/lb
blah blah blah, so about 2 gallons of ice will absorb the heat of 5 gallons fermenting.
assuming everything else is equal and I didnt screw up my math/chem/physics.
I think the contant is 113.25 BTU's per gallon-% alcohol. (alcohol by weight)
one mole of sugar creates 2 moles of alcohol and CO2 and 118 kJ energy.
C6H12O6 → 2C2H5OH + 2CO2 + 2 ATP (Energy Released:118 kJ mol−1)
http://en.wikipedia.org/wiki/Fermentation#Reaction
so if you had 5 gallons of 5% beer, it fermentation would create 2,831 BTU's
if that happens mostly in 2 days, that would be 59 BTU/hr.
the reason i was researching this is to ofset the heat with ice.
specific heat of ice is .5 BTU/lb, water 1 BTU/lb
latent heat of fusion (melting) 144 BTU/lb
blah blah blah, so about 2 gallons of ice will absorb the heat of 5 gallons fermenting.
assuming everything else is equal and I didnt screw up my math/chem/physics.
dang...talk about Beer geek! You need to send Chris Colby, editor of BYO, this stuff and get into the Beer Geek section of the mag. Make all us LBGers all proud!
Just call me Andy!
Lupulin Threshold Shift
lupulin threshold shift \lu·pu·lin thresh·old shift\ n
1. When a once extraordinarily hoppy beer now seems pedestrian.
2. The phenomenon a person has when craving more bitterness in beer.
3. The long-term exposure to extremely hoppy beers; if excessive or prolonged, a habitual dependence on hops will occur.
4. When a "Double IPA" just is not enough
Lupulin Threshold Shift
lupulin threshold shift \lu·pu·lin thresh·old shift\ n
1. When a once extraordinarily hoppy beer now seems pedestrian.
2. The phenomenon a person has when craving more bitterness in beer.
3. The long-term exposure to extremely hoppy beers; if excessive or prolonged, a habitual dependence on hops will occur.
4. When a "Double IPA" just is not enough
Dangs right...my question is how do you plan to distribute the cooling effect of ice consistently with the rise and fall of fermentation temps? Don't get me wrong I like the geek factor of your figures etc. but don't see the pactical application. Glad you want to control temps as it is a fantastic step in improving the quality of your beer but I think a ferment fridge can be found for cheap or free. In you quest if you determine you want an electronic temperature controller let me know and I can get one for you at cost. One way you could make use of ice would be to use a split fermentation chamber. One side is for the fermentor and the other holds a quantity of ice. Take the controller and place the temp probe in the fermenting wort the controller is the powering a fan that blows over the ice and circulates cool air as needed from the ice chamber. Now I know this takes away the geek factor of numbers and formulas but it would be consistant. One geek tool you can pickup to help draw information and track effect is an electronic thermometer from Radio Shack. Capable of giving hi and low temps over a 24 hr period in both indoor (unit in ambient air around fermentor) and out door (probe in wort) I could go on but have probably rambled enough already.
Best of luck!
Best of luck!
