Food and Drink: Would you like to try the beer of the day, sir?: A change in the law has led to 'guest draughts' in pubs and now a flood of appetising innovations. Michael Jackson approves

WE TAKE it for granted that a restaurant regularly freshens up its menu and offers a special. Pubs have begun to feature a 'guest draught' every week or two. But how often should a brewery create a new beer?

Once, a brewer's range lasted a lifetime. Then seasonal specials for summer and winter were rediscovered. Now one beer-maker is offering a new product every fortnight and others are thinking along similar lines.

This would be very difficult for a national giant, geared to test batches, market research and heavy advertising, but even at a local or regional level it requires creativity, skill and confidence on the part of the head brewer, and a good deal of organisation to get the beer into the pubs and to the attention of the customers. Surprisingly, it is the biggest of the regional brewers, Marston's of Burton upon Trent, that is setting the pace.

This year Marston's, famous for Pedigree Bitter, has launched some new beers for two-week periods, ranging from a strongish (5.2 per cent) Winter Warmer to a Luncheon Ale at half the strength; from a Mild to an appropriately nutty Chestnut Ale to a Stout. The current special is a clean-tasting, malty Pale Ale.

These specials, tagged Head Brewer's Choice, are available in more than 300 pubs supplied by Marston's. A publican who wants a Head Brewer's Choice must buy at least two firkins (small casks of 72 pints each), and cannot return unsold beer.

For all the alleged popularity of light-tasting brews, the Luncheon Ale was the slowest mover, and some pubs shifted their stock by discounting it to less than pounds 1 a pint. The Chestnut Ale was the most popular, and the Winter Warmer did well, even at pounds 1.75 a pint in some southern pubs. At the end of the summer there will be a Harvest Ale, then an alternation of the customers' favourites with further styles new to Marston's.

Such choices arise from the legislation that obliged national brewers to admit rival companies' products to their pubs as guest beers. The nationals have gritted their teeth and complied, using their buying power to negotiate tough deals when they bring in beers from regional and local brewers.

Regional and local brewers are not required to offer guest beers, but find customers looking for one. Some brewers are buying beers from each other to meet this need or, as with Marston's, creating their own 'guest beers'.

Although cask-conditioned ales are currently livelier than lagers, the beer market as a whole has been flat during the recession. Marston's also sees its Head Brewer's Choice as a way of maintaining interest in its pubs. This is why the first flurry of beers was launched in winter, and there will be a break during the summer holiday season.

The head brewer Paul Bayley may need a rest from the kettle to devise some new creations, though he admits to no shortage of ideas: 'It has been great, a brewer's delight. Most of us spend years making the same products. At Marston's we like to think of Pedigree as our house classic, but it is wonderful being able to explore the world of beer styles.'

Brewers have infinite chances to create new beers, what with the choice of barley, wheat and other brewing grains; raw, malted or roasted; malts that are pale, amber, brown, crystalline, or kilned like chocolate or coffee; different water treatments; endless hop varieties, with aromas and flavours from the earthy to the flowery to the piney; and changes in yeast strains and fermentation techniques, with their own fruity consequences.

While Marston's is the biggest regional brewer, McMullen's is one of the smaller local companies with 145 pubs, ranging from The Spice of Life in Cambridge Circus, London, to its home town, Hertford. It has just launched a range called Special Reserve, which will go initially into 60 of its pubs. There will be at least four Special Reserves in the next 12 months, starting with an 'India Pale Ale'. Many breweries have an IPA, but few of these bear much resemblance to the originals of the style, and many drinkers are unaware of the designation's meaning.

All beers were either dark or cloudy until maltsters learnt to manipulate temperatures in their kilns and brewers persuaded yeasts to precipitate. Both developments came during the Industrial Revolution, when breweries were becoming much larger. The new 'pale' ales were a translucent copper colour, and established themselves in the days of a huge export trade to the Empire, especially in India.

India Pale Ales were made to relatively high strengths (from 4.5 per cent to 7.0 or more) so that they could enjoy a long, slow, secondary fermentation on their journey. They were also heavily hopped, because the hop is a preservative, though its generous addition would have made for quite a dry beer.

McMullen's has gone to the length of commissioning a maltster to help recreate the product of those days. Malting is a traditional industry in Hertfordshire and East Anglia, and the skills have not been forgotten. French and Jupp's maltings near Ware, Hertfordshire, has produced an amber kilning that helps give McMullen's new IPA a distinctly reddish colour and smooth firmness of body.

The beer contains four different kilnings of malt that give it its accent. McMullen's yeast imparts a considerable fruitiness which seems more evident in this brew, at 5.0 per cent, than in the brewery's less strong regular products. The intention was that this first batch should last for eight weeks, but initial orders suggest five is more likely. I suspect the next Special Reserve will be yet more assertive, and more regional and local brewers will follow Marston's and McMullen's lead.