FOOD & DRINK / Scottish beer in full flower: Heather ale, the secret weapon of the Picts, is still being brewed in Scotland, says Michael Jackson

Chew on this sprig of heather, suggested Bruce Williams. 'Now try this one. See] The bell heather is sweeter, but the ling heather has more perfume. Do you get the spiciness, the astringency?' Such matters are of great importance to Mr Williams. He wants us to enjoy the flavours of this particular flower of Scotland.

People have appreciated the taste of heather since Neolithic times, when it was used in fermented drinks on the island of Rhum. Heather ale was probably the 'magic potion' that rendered the Picts so frightening to the Romans, and it has never totally vanished. Marian McNeill's 1956 classic, The Scots Cellar, offers a lengthy discussion of the drink, and the 1978 Recipes from the Orkney Islands by Eileen Wolfe explains how it can be made.

The tradition of brewing as a culinary activity never died out in Scotland, unlike England. Bruce Williams likes to say that he was 'born in a bucket of homebrew' - his father had a shop supplying malted barley, hops (though not heather) and the equipment to turn them into beer. Today, Mr Williams himself has homebrew shops in Aberdeen and Glasgow. He developed his own kit, Glenbrew, for the production of a typically malty Scottish ale, and sold it in the United States.

Inspired to make a brew that was even more Scottish, he hit upon the heather tradition.

One problem was to find a brewery small enough to make the modest batches he proposed. Heather ale was likely to be an acquired taste, and he did not envisage it flooding the country. The smallest brewery he could find was one established in 1989 in spare buildings in the railway station at Taynuilt, near Oban.

He set out to pick the sprigs of heather - just the flowery tip of the plant, about two inches long - in the nearby Glen Lonan, with his children, Chris, aged eight, and Amy, who is five. But after a whole day's picking, they had only picked enough to make one four-barrel brew.

So he advertised in the local paper, offering pounds 2 a gallon for heather tips and inviting pickers to meet him at Oban pier. At the appointed hour, he found himself surrounded by a dozen triumphantly tired pickers grasping carrier bags, baskets and all manner of containers filled with heather. Since then, he has spent pounds 3,000 on heather, most of it picked by students.

The first small brews were sold on draught in pubs, but to meet growing demand Mr Williams has moved production to a larger brewery, Maclay's of Alloa. With distinctively hard water from the Ochil Hills and - in the past - local coal to fire the brew-kettles, Alloa once produced enough beer to ship down the Forth to Edinburgh and on to London. It was a famous beer town with at least five breweries at the turn of the century.

Of the two remaining, one is owned by Carlsberg-Tetley, the other - Maclay's - is still independent. Behind an 1896 facade in pink sandstone, it has a grist mill from the turn of the century, an 1870s brew-kettle and copper-lined fermenting vessels.

New management has encouraged such revived specialities as a chocolaty Oat Malt Stout, and a seasonal fruit beer using raspberries from Perthshire. Now it is producing 50-barrel batches of Mr Williams's creation, enough to put the brew into bottles for sale in speciality beer shops on both sides of the border.

The beer begins conventionally enough, with barley malted in Berwick; then the sprigs of heather flowers are added as though they were hops, to impart aroma and dryness. They also provide, albeit to a very small degree, further fermentable sugars in the form of nectar. Their perfume is not carried through as assertively as Mr Williams would like, and he has been working on this problem. The hot brew is also filtered through a bed of heather tips. There are five parts of barley malt to one of heather.

The family recipe, which Mr Williams reckons is 10 generations old, calls for the addition of ginger. For a time, he also added shoots of bog myrtle, another traditional ingredient, but found this excessively medicinal. He does, now, employ some hops as a concession to modern times and, in another such compromise, has eschewed the use of sea water.

The beer has a delightfully refractive amber colour, a flowery-fruity bouquet and an almost oily firmness of body with spice and apple notes in its dry, almost wine-like finish. Its alcohol content is 5 per cent, and it is labelled Leann Fraoch, which is Gaelic for heather ale.

I am laying in a case for Hogmanay. Buy now, while stocks last - the ling heather is long out of blossom, and will not flower again for the brewer until July.

For further information, contact: Fraoch Heather Ale, 736 Dumbarton Road, Glasgow (041 339 3479).