| Author |
Message |
    
mark taylor
Intermediate Member
Username: Marktaylo
Post Number: 313
Registered: 06-2003
Posted From: 99.56.138.191
| | Posted on Saturday, November 07, 2009 - 05:19 pm: | 
|
I will be in Mexico soon with limited brewing equipment. So I plan to bottle condition my beer in these large (2 and 4 ltr) plastic soda bottles since I won't be able to bring kegs or kegerator. I have heard that the amount of sugar that you use for priming a corny is less than for 5gal worth of 12oz. bottles. I don't know why this is true but want to know how to figure the needed sugar for 2 and 4 ltr bottles. Thanks for the help.
mark
www.backyardbrewer.blogspot.com
www.thebackyardbrewer.com |
Bill Pierce
Moderator
Username: Billpierce
Post Number: 10905
Registered: 01-2002
Posted From: 24.141.103.148
| | Posted on Saturday, November 07, 2009 - 09:30 pm: |
|
My contention is that the package size has no effect on carbonation. I have primed everything from 7 oz. bottles to 15.5 gallon half-barrel kegs with the proportionally calculated amount of sugar from the formula in an article by Michael L. Hall published in the Summer 1995 issue of Zymurgy. In all cases the carbonation has been accurate.
I have posed questions about the logic for reducing the proportion of priming sugar on both the HBD and the AHA's TechTalk digests. I have yet to receive an explanation.
I say you should prime 2 liter and 4 liter bottles with the same proportion of sugar you would use for any other size package. |
Nephalist
Member
Username: Nephi
Post Number: 217
Registered: 12-2005
Posted From: 71.134.197.136
| | Posted on Saturday, November 07, 2009 - 11:06 pm: |
|
The first (and only?) place I saw a reduced proportion of sugar prescribed for a keg was from Papazian. Another example of outdated folklore? |
Bill Pierce
Moderator
Username: Billpierce
Post Number: 10907
Registered: 01-2002
Posted From: 24.141.103.148
| | Posted on Saturday, November 07, 2009 - 11:50 pm: |
|
Charlie mentioned this in an answer to a question in the current issue of Zymurgy. That was what prompted my post to the AHA's TechTalk. I was kind of hoping he might reply. |
mark taylor
Intermediate Member
Username: Marktaylo
Post Number: 315
Registered: 06-2003
Posted From: 99.56.138.191
| | Posted on Saturday, November 07, 2009 - 11:58 pm: |
|
Bill,
do you remember or have the 'formula' that you reference? For approx 2.5 volumes co2 I typically use 1/2 cup sugar for 5gal. (48 ea 12oz. bottles). If I read you correctly, I could add 1/2 cup sugar to a corny and expect the same volume of co2.
mark
www.backyardbrewer.blogspot.com
www.thebackyardbrewer.com |
Bill Pierce
Moderator
Username: Billpierce
Post Number: 10908
Registered: 01-2002
Posted From: 24.141.103.148
| | Posted on Sunday, November 08, 2009 - 01:26 am: |
|
The priming sugar formula is from a wonderful article, “Brew by the Numbers,” by Michael L. Hall, a physics Ph.D. at the Los Alamos National Laboratory and former member of the AHA’s board of governors, published in the Summer 1995 issue of Zymurgy. The article contains all manner of useful formulas and explanation of the principles they support. It deserves to be reprinted, but unfortunately I am unaware of it being available online.
The relevant formula for the amount of priming sugar is:
PS = 15.195 * VB * (CD – 3.0378 + (0.050062 * T) – (0.00026555 * T^2))
Where:
PS = weight of priming sugar in grams
VB = volume of beer in gallons
CD = carbonation desired in volumes of CO2
T = fermentation temperature in degrees F
This is more than you are likely to want to enter into your scientific calculator, but it fits nicely into a spreadsheet.
The formula is based on the assumption that one molecule of glucose is fermented by the yeast into two molecules of ethanol and two molecules of carbon dioxide. It also assumes that the priming sugar is completely fermentable. It includes the equilibrium volumes of CO2 already in solution based on the original fermentation
temperature.
Note that the amount of sugar is measured by weight. This is far more accurate than measuring it by volume.
Hall’s article doesn’t mention this, but the formula is strictly accurate only for corn sugar as dextrose monohydrate, the form used by brewers and bakers. One water molecule is bound to each molecule of glucose. The chemical weight of glucose (C6 H12 O6) is 180 grams per mole based on the atomic weights, and for water (H2 O) it is 18 grams per mole. Therefore the weight of dextrose monohydrate is 198 (180 + 18) grams per mole, and it is 9.09 percent (18/198) water by weight.
If you prime with table sugar (sucrose), which has no bound water molecule, multiply the calculated weight of the corn sugar by 0.9091, that is, ((100 - 9.09)/100). |
Bill Pierce
Moderator
Username: Billpierce
Post Number: 10909
Registered: 01-2002
Posted From: 24.141.103.148
| | Posted on Sunday, November 08, 2009 - 01:48 am: |
|
To answer your original question, Mark, the calculated amount of corn sugar for priming 5 gallons of beer fermented at 65 F to a carbonation level of 2.5 volumes of CO2 is 121 grams (4.27 oz. by weight). I long ago gave up measuring priming sugar by volume. |
francisco hott
Junior Member
Username: Frano
Post Number: 46
Registered: 09-2008
Posted From: 200.72.191.220
| | Posted on Monday, November 09, 2009 - 03:47 pm: |
|
I use something similar to Bill's
6.5 grams of sugar per liter of beer (I try), Bill's approximately 6,3, but you shouldn't have any trouble from 6 to 7 grams per liter |
The Brewery's Brews & Views