How to Force Carbonate in a Keg

Kegging beer into cornelius or "corny" kegs is great - much less mucking around compared to bottling, and once your beer has finished fermenting and is then transferred to the keg, you can carbonate it much quicker as well when compared to bottle conditioning.

There are a few methods you can use to force carbonate the beer in your keg which are outlined below.

Note that there are a large number of variables that can affect how these processes work - such as beer temperature, any CO2 that's already present because of pressure fermentation etc.

Rapid Force Carbonating

This is the fastest method, but be warned it can lead to over-carbonation if you do it for too long, or at too high a pressure. Like most things in home brewing - a bit of trial and error is likely required.

1. Ensure the temperature of the beer in your keg is at most 4C - the colder the beer, the better it will absorb the CO2 gas.
2. Apply 30psi of CO2 into the gas post of the keg
3. With the gas still connected, turn the keg onto it's side and begin rolling it back and forth on the ground. If you're strong enough, you can try shaking the keg as well.
   You can put a towel under the keg to stop it from scratching if you're on a hard/concrete floor
4. You should hear the gas hissing as it passes through the regulator and into the beer. Moving the liquid within the keg by rolling/shaking it helps to increase the surface area of beer that is contact with the gas which helps it to absorb faster.
5. Continue rolling/shaking the keg for 1 minute then stop and place the keg upright on the ground
6. Leave the keg for 15 minutes to settle then test pouring a beer to check the carbonation level
7. Repeat steps 3-6 until you've got the carbonation at the level you desire. Adjust the time you shake/roll the keg for (Step 5) once you start getting close (go for less than a minute to avoid over-carbonating)
8. Once you've reached the desired carbonation level, vent the excess pressure in the keg using the pressure release valve (PRV) then set to serving pressure - typically 10-12psi

48 Hour Force Carbonating

This is the next fastest method and usually takes 2 days (48 hours) to get close to the required carbonation level

1. Ensure the temperature of the beer in your keg is at most 4C - the colder the beer, the better it will absorb the CO2 gas.
2. Apply 30psi of CO2 into the gas post of the keg
3. Leave the gas connected at 30psi for 48 hours
4. After 48 hours, vent the excess pressure in the keg using the pressure release valve (PRV) then set to serving pressure - typically 10-12psi
5. Pour a test beer and check. You can leave at serving pressure if further carbonation is required, or otherwise boost to 30psi for another short period of time then test again

Set & Forget

This is the simplest and most reliable way to carbonate your beer - and also eliminates any risk of over-carbonating your beer

1. Ensure the temperature of the beer in your keg is at most 4C - the colder the beer, the better it will absorb the CO2 gas.
2. Apply 10-12psi of CO2 into the gas post of the keg
3. Leave the gas connected for 7 days then test pouring

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