This article is from the Real Ale FAQ, by with numerous contributions by Brett Laniosh others.
A: Often your best bet is to ask your local publican. If you think that
four and a half gallons is enough then try to get hold of a polypin. This
is a plastic bag inside a cardboard box and is often non- returnable, so
there are no worries about a deposit. All you need to do to dispense the
racked-beer (see glossary) is to turn on the already fitted tap.
If you have a place that will serve as a cellar for three days, (a kitchen
might just do if you can keep the beer at 14/15 degrees centigrade (56deg.
F) and make sure it won't get knocked as people pass, then you can keep
the beer as a publican would do. You need advice on how and when to tap
and spile the cask as well as the tools for the job. This is fun if you
have the time and the friendly publican. Alternatively you might want to
pick up the beer in the morning of the event and serve in the afternoon or
evening. This wouldn't normally be possible because the beer wouldn't
settle but the way to do it is to have a 're-racked' cask. Your friendly
publican drains a cask that has been maturing in his cellar into a freshly
cleaned cask on the morning of the event. Your re-racked cask can be
manhandled and tapped minutes before serving, but must be consumed on the
A carry keg with its pressure safe top is an ideal way to take a small
amount (typically four pints) of beer home. When the beer is being
transferred, make sure that any sparkler is slackened off or removed,
otherwise it froths up and by the time you get the beer home, it's already
going flat. If you can persuade the barkeeper to dispense directly into
the carrykeg, that's quicker and disturbs the beer less, but they
generally insist on measuring the beer out into pint glasses, then
decanting then into the carrykeg (hence the funnel). But a properly
maintained beer engine should be capable of dispensing measures of one
quarter pint or one half pint in each pull.
It's not essential to buy 4 pints every time though the beer does keep its
condition better if there's less airspace. But if you only want a couple
of pints, that will keep fine for an hour or so on the way home. Generally
speaking, beer in a carrykeg should be consumed within 24 hours.
Another possibility is the PET plastic pop bottle, available from any good
supermarket in 1, 1.5, 2 and 3 litre sizes. Of course you do have to make
sure that you first of all drain them and cleanse them of any sugary
residue but they are built to withstand pressurised gas and they are
usually cheaper than an empty carrykeg. Also the neck is narrower so more
care has to be taken in filling a pop bottle.
Remember that without a licence you can't sell beer. Without a licence you
can only serve beer at a private party. A wedding falls into this category
but a club event may not.