Soak up some fundamental draft beer information! From keg dimensions to pressure settings, KegWorks knows it all. Quench your thirst for knowledge and become a smarter, more educated draft beer connoisseur.
Direct Draw Draft System/ Draft SystemTechnical name for specialized equipment that is built specifically for dispensing keg beer from a temperature-controlled environment, through the use of compressed gas. Direct draw draft systems may be housed in a kegerator, walk-in cooler or converted refrigerator. Boil down all that fancy talk and youíve got a system to keep your beer cold and get it into your glass.
Any type of beer that is drawn from a large vessel. Kegs arenít the only "vessels;" the term "draft beer" includes cask ale too.
KegMetal container used for storing and dispensing pressurized liquids (like beer, for example). Kegs come in a range of standard sizes. A single hole centered on the top of the keg and a two-way valve allows liquids (like beer) to be added and removed from the keg.
Non-pasteurized beer that is dispensed from a keg through the use of gas pressure.
Below are volume and dimensions for Standard US Kegs
Holds 15.5 gallons
Or approximately 165 12-ounce bottles
Weighs 161 pounds full
24" high with a 16" diameter
Holds 7.75 gallons
Or approximately 82 12-ounce bottles
Weighs 87 pounds full
12-13" high with a 16" diameter
Holds 5 gallons
Or approximately 54 12-ounce bottles
Weighs 55 pounds full
24" high with an 11" diameter
Note: US keg dimensions may vary slightly by keg manufacturer and brewery. European kegs vary in size, but are similar to US sizes.
Pressure is important when it comes to draft beer. It's what keeps your beer carbonated and tasting fresh, and helps to push the beer out of the keg and into your pitcher or pint! Having too much or too little pressure will affect the way that your beer is dispensed and you won't be able to enjoy it to its full potential, so make sure to pay attention!
About Head Space
As CO2 enters a keg it displaces your beer at a constant pressure. When you open the tap/faucet, beer flows out of the keg and into your glass thanks to a push from the CO2. Not only does the gas encourage the beer to leave the keg, it replaces that beer by occupying the space that otherwise would be empty. This empty space in the keg is called "head space." The CO2 fills the head space and maintains the pressure inside of the keg at the PSI set on your regulator. This constant PSI keeps the beer well carbonated by preventing the CO2 that comes dissolved in the beer from the brewery from leaking out.
Keep it Straight
Your CO2 tank must be stored upright or it wonít work properly. Storing the tank improperly can also cause expensive damage to your regulator.
Find the Magic Number
In general, most US produced ales and lagers should be dispensed at 10 to 12 PSI. Stout and other nitrogen reliant keg beers are usually dispensed at 25 to 30 PSI.
For the specific dispensing pressure for a particular keg, check with your local keg distributor.
Too much pressure will initially result in you beer coming out of the tap very quickly and very foamy. Essentially, your faucet will turn into a beer fire hose. In addition, if your beer is over carbonated, the foam will appear tight and have large bubbles.
If you recognize the problem, it is easy to fix: promptly adjust your regulator pressure to the proper lower level, and draw a few foamy pitchers or bleed some of the extra pressure off by using the relief valve on the coupler. These measures will allow the system to balance it out again.
If the pressure is left too high for longer than 24 hours, CO2 will be forced into the beer resulting in permanently over-carbonated and excessively foamy beer.
Keep it Calm
Too little pressure will also cause the beer to become foamy, as the CO2 breaks free from the beer as it enters your glass. If the pressure is not raised to the appropriate level, your beer will eventually become flat.
A telltale sign of low pressure is when foam or bubbles visibly rise into the beer hose. If your beer is indeed under carbonated, the foam will appear loose (sometimes described as "soapy" looking) with small bubbles.
To correct this problem, you should first make sure that your CO2 tank isn't empty and is turned on. Then, check to see to what level your regulator
is set. If your tank is functioning properly, your regulator
is set to the right number and there are no obstructions in the air line
, it is possible that your regulator or gauge needs to be replaced. Regulators do wear down and should generally be replaced every 4-6 years.
Always give your kegs time to settle down after transport and travel. If you donít, youíre likely to experience excessive foaming when you tap it. Remember that the beer inside of a keg is carbonated, so moving or shaking it will cause it to foam Ė just like a giant can of beer would. We recommend letting your keg sit for an hour or so after you move it.
Keep it Cold
Keg beer is not pasteurized, so itís got to stay cold to stay good. A general rule is to think of the beer inside of your keg the same way that you think of milk: it needs to be refrigerated at all times. Keep your kegs between 34 and 40 degrees Fahrenheit and your beer will stay fresh and delicious.
Keep it Fresh
Speaking of fresh, the beer inside a keg will stay fresh for 30 to 45 days after it has been tapped. It's difficult to pinpoint an exact amount of time, as a keg's "shelf-life" depends on the brand/style of beer and its storage conditions. Generally, hoppy beers and beers with higher alcohol contents will last longer because the alcohol and hops act as preservatives and inhibit bacteria growth.
Keep it Clean
When beer does go bad too quickly, the culprits are almost always bacteria or oxygen. Unfortunately, bacteria will eventually spoil unpasteurized keg beer - even when the keg is kept in the most ideal storage conditions.
Modern scientists have discovered that the only way to beat the bacteria is to drink all of the beer in your keg, before the bacteria has a chance to ruin it. KegWorks research has found that good friends are usually willing to help out, should you require critical consumption assistance.
Bacteria's partner in crime doesnít appear dangerous, but don't be fooled. Oxygen is particularly harmful to kegs that have been tapped with a hand pump. The hand pump forces air (containing oxygen) into the keg, which in-turn forces the beer out. This is good. However, as soon as the oxygen is introduced into the keg, it causes a chemical reaction called oxidation.
Oxidation will cause the beer inside of a keg to go flat and the beer may also develop a sour taste. This is why a keg tapped with a hand pump should be consumed with in 24 hours. Thankfully, neither of these processes renders beer harmful to humans, but your beer won't taste fresh and may be flat.
Thirsty for more?
Check out "How Draft Beer Systems Work"