A national treasure, or a joke, whichever way you look at it, this week is National Spam Appreciation Week. NICK MORRISON looks at the history of the 'miracle meat'

IF you were to walk into a caf and find that everything on the menu had one thing in common, it might be a sign to walk straight out again. But if that one thing were Spam, then a legend is born.

More than any advertising campaign could possible have managed, Monty Python's Spam sketch has ensured Jay C Hormel's invention has forever a place in our hearts. Its name only has to be mentioned for entire rooms full of people to start singing "Spam Spam Spam Spam, Spam Spam Spam Spam," or to come out with jokes along the lines of "I'm pink, therefore I'm Spam" - well, you get the idea.

Generations of children have grown up knowing - and sometimes even loving - these pink lumps of meat, packaged in distinctive rectangular cans. Whole recipe books have been devoted to finding new and exciting things to do with Spam, probably.

Spam was developed during the 1930s in the US and was first marketed as Hormel Spiced Ham, but sales didn't really take off until it was renamed Spam in 1937 and advertised as "the miracle meat". Three years later it featured in the first singing TV ad, with lyrics to the tune of "My Bonny Lies Over the Ocean". But its real break came during the Second World War. Unlike beef, Spam was not rationed in America and became a staple of the wartime diet, and in 1941 it arrived on these shores, as part of the US Government's Lend-Lease agreement to help towards the Allied war effort.

It was first made in the UK under licence in the late 1950s, and is now produced in Australia, Denmark, the Philippines, Japan, Taiwan and South Korea, as well as America. By 1959, one billion cans of Spam had been sold, and enough has now been produced to go round the Earth two-and-a-half times. By the 1960s it was a staple on every school meal menu.

Spam even has its own museum, in Austin, Minnesota, which opened in 1991 and attracts more than 60,000 people a year. And lest anyone ever accuse Spam of being a relic of the past, in the 1990s Hormel introduced a new version to fit in with changing consumer patterns, named Spam Lite.

It may not be the most glamorous food in the world, and it may be difficult to imagine it featuring on the menus of the best restaurants, but a world without Spam would be a poorer place indeed.