When is a stilton not a stilton?

A true Stilton cheese must be made with the milk from one of half a dozen herds based around the Leicestershire village of Long Clawson.

Doubts over the authenticity of the famous blue cheese first surfaced a generation ago when it emerged that much of what was being passed off as Stilton in British stores was in fact Danish Blue.

The Stilton Cheese Makers Association was established and in 1986 it registered the names "Stilton" and "Stilton Cheese" with the Patent Office's Certification Trade Mark register.

A decade later, Stilton was also registered with the European Commission as one of 30 British products among nearly 500 protected regional foods.

The commission drew up the register after deciding that products that had become well known outside their area of origin were suffering from unfair competition at the hands of imitations.

The ruling infuriated the Danes, who for years had bought a cow's milk cheese called feta, which was now deemed the exclusive produce of Greece.

It was France and Italy who were most active in looking to guard the reputation of their regional delicacies.

France, which has its own appellation controllee system, registered with the EC 32 regional chickens and 36 cheeses, as well as specialities like Pink Toulouse Lautrec garlic and Provence lavender oil.

Among the products registered by British producers were Orkney beef and lamb, Scotch beef and lamb, and Shetland lamb.

Cheese featured most prominently on the British list, but the only fresh produce registered was Jersey Royal Potatoes. But local brewers were able to protect Newcastle Brown Ale, Rutland Bitter, Kent Ale and Herefordshire Cider.