Attend any cellar management course and one of the lessons that will be driven home to you over and over again is that you must clean your beer lines every seven days.
The cost of not sticking to this discipline is a whole range of problems from fobbing to hazy beer to off-flavoured pints. Yet research suggests that 25 per cent of licensees fail to clean their lines on a strict weekly basis.
From one point of view you can understand why. Line cleaning is a chore, of course, and it costs money too - not so much in cleaning materials but in lost beer, which is wasted at either end of the clean. Many licensees calculate that the less line cleaning they can get away with, the more money they can save.
But it's a false economy. Fobbing wastes beer too, bad pints might be sent back and, in the longer term, the pub could get a bad reputation for its beers and lose custom.
Over the years plenty of research and development has gone into finding ways of making line cleaning easier and more efficient, and of extending the seven-day cycle. So far this has made little impression on the working routine at most pubs, and brewers continue to bang away at the weekly line clean message.
With beer quality now higher up the agenda, however, efforts are being stepped up. Greene King currently has a few alternative line cleaning systems on trial in its estate, and Marston's Inns & Taverns continues to operate the Stayclean system on keg beer lines in some former Banks's pubs. A couple of Barracuda outlets, in Derby and Newark, also have it.
Stayclean, which claims to extend the line cleaning cycle to 28 days, has been around since 1993 and it's been a long, hard slog for designer Tony Allen to gain acceptance for it in the UK pub trade. Hotels have been a different story, though. The system is now running in 27 sites in the De Vere estate, and also has a presence in Florida and France.
The technology behind Stayclean sounds slightly far-fetched when you first encounter it. Radio waves are pulsed down the beer lines creating a magnetic field that holds in suspension yeast particles that would normally coagulate and stick to the line.
"Hotels have been a good market for us because they tend to have a much slower rate of sale than pubs, which can give them more problems because beer is held longer in the lines," says Tony.
An eight-week trial at famous Midlands golf venue the Belfry - where beer lines to some bars can hold eight pints - has suggested it could save 7,500 pints of beer over a year by using Stayclean.
"On average, we used to clean our beer pipes three or four times each month depending on usage," says the hotel's head of food and beverage operations Martin Taylor. "As well as being extremely labour and time intensive, the process wasted a significant quantity of beer, resulting in us literally pouring money down the drain.
"Since installing Stayclean, we've been able to reduce cleaning to just once a month with no impact on beer quality. We've been able to free up valuable staff time and we're saving approximately 576 pints each month which has an obvious bottom-line benefit."
Systems such as Stayclean are designed simply to reduce frequency of clean. Licensees using it continue to clean in the traditional way but less often. There are other systems on the market, though, that aim to ease the burden by automating the process to varying degrees.
Automatic Beerline Cleaning Systems, which has perhaps been around the longest, has launched a new compact model that claims to replicate a traditional clean.
Features include a simple one-button operation without any confusing control boxes on the cellar unit or behind the bar. A built-in counter monitors the number of time the system has been used.
Beer wastage is reduced by attaching 'empty keg simulators' and selling the beer which is normally thrown away during a line clean.