Introduction to Kegging

Introduction to Kegging

By Paul Kervran

So why keg?

The answer to this question typically comes down to a matter of convienience. The ease of cleaning and sanitizing one vessel vs. 50 bottles for a typical five gallon batch of homebrew is often the compelling reason to make the shift from bottling to kegging.

Other advantages:

· It takes less time to fill a keg than bottles

· Ability to force carbonate beer eliminating weeks of waiting for bottles to carbonate with priming sugar

· Minimal / no sediment when beer is force carbonated

· Kegs make excellent secondary fermenters minimizing oxidation, light damage and allowing for closed environment transfers to the serving keg

· Beer on tap tastes great

Basic Kegging Equipment Needed

The first item you will need is a used soda keg or “Corny” keg. The name Corny is comes from Cornelius, one of the primary manufacturers of soda kegs. As the soda industry has moved from kegs to syrup in a box, these kegs have become readily available to homebrewers at reasonable prices. The standard size is five gallons, although three and ten gallon sizes are also available.

There are two basic types of kegs, Ball Lock (Pepsi / general beverage) and Pin Lock (Coke). These designations simply refer to the type of connectors on the gas and liquid posts. Both are perfectly suitable for homebrewing purposes, although ball lock kegs and parts seem to be a bit cheaper and more available than pin locks. For simplicity sake, homebrewers should decide on one type to eliminate the need for different types of connectors.

The decision on how many kegs to buy will be primarily dictated by the amount of brewing you do but a good number to start with is two. Two kegs will allow you to have one on tap and one conditioning and ready to go when the first keg is done.

When you first get a keg it will need some special cleaning and attention. For further details see the section titled “Cleaning Your Keg”.

A CO2 tank is the next necessary piece of equipment. Standard sizes are five, 10 and 20 lb. sizes. These tanks can be made of either steel or aluminum but the difference is purely cosmetic. You will need to decide whether to purchase or rent a tank. If purchasing a tank you will need to ensure that the certification date stamped at the top of the tank is current. Tanks need to be hydro – (or pressure) tested every five years and can cost $20-$30 for re-certification before they can be refilled. Tanks can be refilled or rented from sources such homebrew, welding supply and fire extinguisher shops.

To use a CO2 tank, you will need a regulator which reduces the pressure of the tank from about 800 psi to a usable 10 to 30 pounds needed to for force carbonating and dispensing beer. Regulators can have either one or two gauges. Either type will work for dispensing beer. On two gauge models, the first gauge, which is actually the more important of the two, shows dispensing pressure. The second gauge, which is not as critical (or useful), shows tank pressure which is a rough estimate of how much gas is left in the tank. For the most part though, this gauge will register as full until the very last moment when it moves into the “almost empty” red zone.

One important consideration for a regular is to make sure you have a check valve installed on it. If you were to hook up a regulator/CO2 tank to a keg which had a higher pressure than the dispensing pressure of the regulator, beer from the keg can back up into the regulator and damage it.

Quick disconnects are the fittings that attach to the liquid and gas posts on the corny keg. The black fitting, or liquid fitting connects to the “out” post on the keg. The gray or Gas fitting (remember G = Gas) attaches to the “in” post. The in or gas past is easily identified by notching or a star shaped base to differentiate it from the liquid post.

An important lesson is to not mix up your connections. If you force a gas quick disconnect on a liquid post you will more than likely be hacksawing it off later. They are not interchangeable!

The last items needed for a basic setup, is a picnic (aka Cobra) tap and hose for the beer and gas. The standard size hose for gas is 1/4 inch. If you plan on force carbonating and working at high pressures (30 lb.) then braided hose is a good choice as it is more durable and less likely to stretch or burst. While 1/4 inch hose can also be used for beer, 3/16 inch has become very popular as it restricts the beer flow more and as a result tends to minimize foaming when serving.

Cleaning Your Keg

Unless you plan on serving a Root Beer Pils or an Orange Crush Pale Ale, you need to clean up and refurbish your newly acquired keg. Before concerning yourself with the keg innards, it’s not a bad idea to clean up the outside of the keg. Chances are, unless you’re lucky, the keg is covered with an assortment of “Property of Pepsi” and a host of other such labels. These labels were intended to be permanent labels so don’t expect them to fall off with a simple soaking.

Both WD40 and Goo Gone are effective at dissolving the adhesive of the stickers. Use of these products along with a razor blade will assist in scraping the labels off. A scrub pad will help to remove any residual glue. If you really want to shine up your keg and get rid of any discoloration or minor rust spots, Bar Keeper’s friend (an acid based metal cleaner) works well.

Now that the outside has been clean up, the important part begins. To thoroughly clean up and refurbish a keg you will want to disassemble it to clean all keg components. A 12-point 11/16 inch deep socket is the typical size socket for removing the gas in and liquid out posts. Inside the posts are little springy valves called poppets. These should be set aside for later soaking.

Since keg gaskets can permanently absorb soda aromas / flavors and may not be in the best of condition you should always get a gasket set when you get a used keg. A complete set of gaskets will include a lid gasket, two dip tube gaskets and to post O-rings. The keg should be filled with a cleaning solution of TSP or PBW. Also soak all parts including the posts, poppets, dip tubes etc. in the cleaning solution. A dip tube brush is a handy tool to ensure you get any potential nasties and buildup out of the tubing. After a thorough rinsing the keg is ready to be reassembled and sanitized for use.

Rule number one for sanitizing kegs is not to use bleach. Bleach reacts with stainless steel and can cause pitting and even holes to form in your keg if left in contact too long. Star San or Iodophor are suitable sanitizers for kegs.

Filling Your Keg

An advantage to kegging over bottling is the ability to minimize oxidation when transferring beer from your secondary fermenter. This accomplished by sealing up a sanitized keg and pressurizing it with CO2. The pressure release valve on the lid is pulled to release pressure and the process is repeated two or three times. Once this step is complete the pressure is again released and the lid removed. As CO2 is heavier than air, a protective blanket of CO2 will remain to minimize oxidation when the beer is transferred. At this point beer can be racked to the keg with little worry as any splashing that does occur will be in an oxygen free environment.

Force Carbonating

To set the record straight, kegs can certainly be carbonated naturally with priming sugar the same as bottling. Carbonating this way however takes away some key advantages to kegging, namely minimizing sediment in the finished product and the ability to quickly carbonate. As CO2 is more readily absorbed into a cold liquid, chilling the keg of beer first is in order. Depending on the level of carbonation desired, the keg can be connected to gas at 10 to 15 pounds and allowed to sit for several days to a week. To accomplish quick carbonation, set the regulator at 30 pounds of pressure and shake the keg vigorously. The higher pressure and shaking will help the CO2 to get into solution quickly. Be warned that while this quick carbonation method works well, the keg should be allowed to sit for several hours before serving to allow the gas to stabilize in solution or excess foaming will occur.

If you wish to get scientific in your approach to carbonating, you can refer to the chart below. Keep in mind most commercially packaged beer is in the 2.3 to 2.8 volume range. British ales would be at the low end of the scale while Weiss beers and certain Belgian styles would be at the high end of the carbonation chart.

Keg Carbonation Chart

Pressure Required For Desired Carbonation