Force Carbonation & Carb Table

This is the best part about kegging, no more priming and no more waiting for the beer to carbonate. First, determine the desired carbonation level for your beer. This is measured in Volumes of CO2. The definition of this term is not that important, but what is important is to realize that the higher the volume measurement, the higher the carbonation level. Here are some typical carbonation amounts, listed in volumes of CO2 for several beer styles:

British-style ales 1.5 - 2.0 Porter, stout 1.7 - 2.3

Belgian ales 1.9 - 2.4 European lagers 2.2 - 2.7

American ales & lagers 2.2 - 2.7 Lambic 2.4 - 2.8

Fruit lambic 3.0 - 4.5 German wheat beer 3.3 - 4.5

There are two main factors to determine the number of volumes in beer: pressure and temperature. At a certain pressure and temperature, beer will have a given carbonation amount measured in volumes of CO2. These values can be seen in the chart at the bottom of this page. The temperature of the beer is usually the serving temperature. In my brewery this is about 42 - 45 F. If you want to carbonate a beer to 2.2 volumes at 43 F, just go down the vertical column to 43 F, then across until you find the desired carbonation level. In this case, I will have to pressurize to about 11 - 12 PSI. The values highlighted in yellow are typical values for most styles (at least in my brewery). I know this table is hard to read, so I've made the original MS Excel file available here. There are 3 sheets on this table, a worksheet that automatically calculates volumes of CO2 based on your inputted temperature and pressure; the full blown table; and a graph charting volumes vs. pressure for temperatures from 30 - 70 F.

There are several methods for force carbonation. The first is to chill your keg of beer down to your serving temperature, then dial up the pressure to achieve your desired carbonation level, leave the regulator set, and wait. Over time, the CO2 will dissolve into the beer until it comes to equilibrium. This can take several days to a week to occur.

The other method is much quicker. First, chill the keg to serving temperature (42 - 45 F). This lets the CO2 dissolve much easier. Then set your regulator to 25 - 30 PSI. Sit in a chair and lay the keg across your knees with the CO2 line still connected. Now , grasp both ends of the keg and shake vigorously while you slowly count to 100. As you are shaking, you will be able to hear CO2 flowing through the regulator. After you reach 100, stop shaking, disconnect the gas line, and set the keg into the refrigerator for several hours. This will give the beer time to settle. After a few hours, bleed the pressure down to serving pressure and draw a glass. You will have to adjust this procedure for your brewery depending on how carbonated you like your beer. Colder temps will mean more CO2 at the same pressure, higher temps will be less CO2. By jacking up the pressure and shaking, all we are doing is forcing the CO2 into solution quicker. Take care not to shake too long or you will over carbonate your beer. For parameters outside the typical range, use the chart below to achieve your desired carbonation level.

I would not recommend the carbonation stones. Just personal preference. It's just more hardware to deal with. Stick with the shake method.