Force Carbonation

1. It's a good idea to clean your Cornelius keg every time before re-using it. To do so, disassemble all of the fittings, sanitize the keg as you would any other piece of homebrewing equipment and rinse it thoroughly with hot water before using it.

   Iodophor is widely recommended to clean Cornelius kegs, but everyone's got their own opinions and processes. Regardless, bleach should not be used to clean your Cornelius keg (or anything stainless steel for that matter) as it is corrosive to stainless steel.

2. Once the keg has been cleaned and rinsed, run CO2 into your keg for a few seconds, then gently siphon the beer from your fermenter into the keg.

   CO2 is heavier than air, so the CO2 will displace the air and allow the beer to be siphoned into an oxygen-free tank. This isn't absolutely necessary, but it reduces the risk of oxygenation or beer-spoiling bacteria getting into your keg.

3. Seal the keg, add about 5 psi of pressure and check all fittings and connections for leaks.

   The point is make sure you have a nice, tight seal everywhere on your kegging system so that you're not leaking CO2. Place a drop of beer or liquid soap on every single place where one piece of equipment connects to another - if you get foam, CO2 is trying to escape through that connection. If you didn't fill the keg with CO2 before adding the beer, pull the relief ring or lever to allow air out of the keg at this point. Do this several times waiting several minutes between each pull. This removes beer-spoiling oxygen from the keg and replaces it with CO2.

4. Increase the keg pressure to the desired level (approximately 10 psi if you don't have another preference) and let the keg sit for at least a week before checking to see if the beer is sufficiently carbonated.

   There are several ways to make sure your beer carbonates quicker. First, the colder the beer, the faster the CO2 is absorbed into the beer. I can't explain the physics, just cool your beer in the fermenter the night before racking it to the keg. Second, the more pressure there is in the keg, the faster the CO2 is absorbed into the beer. Many people double the intended dispensing pressure in the keg to cut the carbonation time significantly. (Just remember to reduce the pressure in the keg to the preferred dispensing pressure by venting it when you're done shaking the keg!) Finally, the more surface area of the beer the CO2 touches, the faster the CO2 is absorbed into the beer. Place the full keg on your lap, turn on the CO2, disconnect the beer line and shake the keg until you can no longer hear the gas running into the keg (which means that CO2 absorption has max'd out for the moment). Many people do all three - cool the beer, crank up the pressure and shake the keg - to obtain fully carbonated beer in hours instead of weeks!

Beer can also be carbonated in a keg with sugar, or "bulk primed," by adding 1/3 cup of corn sugar to the beer in the keg and waiting a few weeks for it to carbonate instead of force-carbonating the beer with CO2, but if you have the right equipment and can carbonate the beer in days or even hours, I don't see the point in this. This method would only be necessary if you didn't have a CO2 tank.