Ask the Experts: Kegging Beer

Homebrew expert Brad Smith, author of the Beersmith homebrewing software and the voice behind the Beersmith podcast, offers advice on kegging your homebrew.

Brad Smith Oct 30, 2017 - 4 min read

Ask the Experts: Kegging Beer Primary Image

A Craft Beer & Brewing Magazine reader recently asked us the following question:

I’m thinking of switching from bottling my beer to kegging. What do I need to begin kegging beer?

Kegging beer offers a huge time savings versus bottling. Stainless-steel kegs are very easy to clean, and you can force carbonate your beer, which gives you better control over the exact carbonation level. The only downside is that you do need some kind of refrigerator—either space in an existing refrigerator or a dedicated freezer/refrigerator or kegerator to store the keg because proper serving pressure requires refrigeration.

Craft Beer & Brewing Magazine® has a great class on kegging your beer, but here are the basics. The most basic system consists of a keg, a CO2 tank and regulator, two hoses with connectors, and a simple plastic picnic tap. The most popular kegs are 5-gallon (19 l) Cornelius (soda) kegs, which are about the size of a scuba tank, though 2.5- and 1.5-gallon mini-kegs are good options if your refrigerator space is limited. Kegs may have either ball-lock or pin-lock connectors, which refers to the style of connector used on the in and out ports of the keg.

A CO2 tank provides carbon dioxide gas to carbonate and also dispense your beer. CO2 will not spoil your beer the way oxygen will, so a CO2-pressurized keg will store for many months. Most beginner kits come with 5 lb (2.3 kg) CO2 tanks, and they are shipped empty. You can fill or exchange the CO2 tank at your local beverage-gas supplier. For a small additional fee, you can usually upgrade to a 10 lb (4.5 kg) or 20 lb (9.1 kg) tank, which will last a lot longer and is generally about the same price to fill.

You will also need a pressure regulator attached to your CO2 tank. The regulator lowers the pressure from roughly 800 pounds per square inch (psi) to a typical beer-serving pressure of 11–13 psi. A gas line connects from the regulator to the input on the keg to pressurize the keg. The output of the keg connects to a beer line that runs to the tap. Most beginner kits come with cheap plastic “picnic” taps (at right), though you can also purchase stainless-steel pub-style taps to install on your refrigerator door or bar.

To use your keg system, first assemble it and check for leaks by applying pressure and spraying the various fittings with Starsan or soap/water, which should bubble if a leak is present. Clean and sanitize your keg and then siphon your finished beer into it. Once the keg is full, seal it up and apply CO2 pressure. Use the purge valve at the top to purge the oxygen from the keg and replace it with CO2. To carbonate the beer, put the keg in the refrigerator and set the pressure to about 12 psi. If you leave it under pressure and refrigerated, the beer will fully carbonate within 5–7 days. After that, just serve and enjoy!

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