It looks like this:
We recommend either a a King Keg (in top tap & bottom versions) or the Economy 25 litre barrel.
King Keg Economy Barrel
THE KING KEG
Probably the most famous barrel on the market. When it was launched a few years ago it set new standards. The main features of this blow moulded barrel is the sturdy construction, with the large neck opening. This allows you to put your hand in to clean the inside. The large top comes complete with a rather special valve. This allows the release of excess gases which build up during the secondary fermentation (the priming process, see later). It also allows for the injection of additional CO2 gas (again see later). It is quite simple in operation, having a channel which goes straight down the length of the valve allowing gas to enter into the barrel by blowing the small rubber temporarily away from the pin it is covering. When the gas is stopped being injected it reseals, preventing any infection. The rubber in the middle of the valve is designed to expand when the pressure inside the barrel rises above 8 - 10 psi. Again, a channel from the base of the valve joins up with the rubber in the middle. Once the pressure settles down this will then reseal itself. The rubbers will need replacing every 6 months.
With the King Keg you have a choice of two: Top Tap version (code 7064) Bottom Tap version (code 7066) TOP TAP (7064) This has a float which allows you to draw off the beer from the top. Naturally the beer will clear at the top first, so you actually get to drink clear beer quicker with this version. You can also stand the barrel on a worktop or floor as you don't need to overhang a surface to get your glass under. As the tap is ľ of the way up it's got plenty of height for your "pint tumbler". BOTTOM TAP (7066) We have to say this is the more popular version as it is easier to use, and less to go wrong. You do however need to make sure you have somewhere to put it (over hanging a work surface). As a lot of people want to allow the beer to mature (6 weeks plus) the clearing is not really an issue.
25 Litre (7062) This again is a great barrel but only has a 50mm (2") cap which is fitted with a pressure valve (see earlier). You can't get your hand in to clean it but with the modern cleaner/steriliser (like the Ritchie one) this is not so important. The thing that people like about this barrel is the simplicity of it.
COMMON TO ALL BARRELS
Once again the beer kit manufacturers will recommend on the kits what to do, but the idea of priming is to get a secondary fermentation going. This is done by adding sugar to the beer which has been transferred from your bucket. Whilst the initial fermentation finished in the bucket (all the sugar has been converted into alcohol), it is possible to get this going again by adding more sugar. There are still yeast cells floating in the beer, and by adding the sugar the yeast will start to convert this into alcohol. As this happens CO2 gases are given off - which create the pressure in the barrel. This allows the beer to become slightly carbonated, and gives sufficient pressure so when you turn the tap on beer comes out of the barrel.