Truffle that cost £28,000 leaves a bitter taste after restaurant lets it rot in fridge

Its Latin name loosely translates as "food of kings". Such is the mystique that surrounds tuber magnatum that it can cost as much per ounce as gold and was considered by the medieval church to be the work of Satan.

Its Latin name loosely translates as "food of kings". Such is the mystique that surrounds tuber magnatum that it can cost as much per ounce as gold and was considered by the medieval church to be the work of Satan.

So when Enzo Cassini clubbed together with A-list regulars at the London restaurant he manages to spend £28,000 on the world's second-largest Italian white truffle, he could be forgiven for assuming he was on to a winner.

The arrival of the 850g (1lb 14oz) fungus at Zafferano, the Michelin-starred Italian restaurant in Knightsbridge favoured by gourmand glitterati from Madonna to Bill Clinton, drew salivating admirers from Paris and Madrid.

Queues formed in search of the taste described by Mr Cassini as "earthy, sexy and an aphrodisiac", available at a cost of £600 per micro-sliced sprinkling from a mandolin grater.

The media were tipped off that among those waiting to sample the truffle were Gwyneth Paltrow and the Russian billionaire Roman Abramovich, who were thought to have been part of the syndicate that bought the truffle at a charity auction two weeks ago.

Even when the head chef, Andy Needham, left the monstrous mushroom in a refrigerated safe for four days, taking the keys with him on holiday, staff remained confident that the stage was set for a publicity coup

Imagine the horror, therefore, when Mr Needham took the tartufo from its storage place this week and found Zafferano's "earthy, sexy" pride and joy had lost its allure. Put bluntly, it had gone off.

Speaking yesterday as he served lunchtime diners, a downcast Mr Cassini said: "The problem was that after we received the truffle, it was displayed for four or five days because so many people wanted to come and see it. We had people from France and Spain.

"Then Andy had to go away for a few days. When he came back, we found our poor little truffle had gone past its best. It was very sad."

The 34-year-old manager, who bid some of his own money towards the elite fungus, refused to blame his chef for the costly mishap.

He said: "Normally it would have been fine. Andy realised he had the keys to the safe with him when he got on the plane but we both thought it would be all right.

"Unfortunately it was not. The truffle is like a fruit. When it is ripe, the smell is beautiful, like the forest floor. But then it becomes extremely pungent and finally it is bland and bitter."

The Italian white truffle, considered by connoisseurs to be superior to French black truffle, was found by a farmer and his dog near San Miniato, the Tuscan village some 25 miles from Florence. Its size was surpassed only by another San Miniato truffle, weighing 1.08kg, which was sold to a New York restaurant early last month.

Restaurateurs and truffle producers have worked hard to maintain the mystique around the fungus, which grows a few centimetres under the ground among the roots of oak, poplar and holm oak trees.

Among the qualities attributed to it is a high content of a chemical virtually identical to androstenone, a sex hormone secreted by the male pig.

Mr Cassini and his syndicate of backers, which is also thought to have included a number of bankers from Goldman Sachs, bid for their truffle via a satellite link at a charity auction. The money raised went to Children in Crisis, founded by the Duchess of York.

The idea had been to serve the bidders with Zafferano's truffle-flecked signature dishes such as veal tartare, omelettes and cheese fondue topped with shavings of the fungus.

In the end, the only individual to sample the truffle was a newspaper writer who declared its flavour "halfway between that of a smoked cheese and strong mushroom". The journalist, Nick Curtis, of the London Evening Standard, said: "I don't want to rub it in, but it really was remarkable."

Zafferano staff have chosen to return the truffle whence it came by burying it in Mr Needham's garden in Fulham, west London. Mr Cassini said: "It died a very happy truffle - back in the ground, unsliced. We piled some stones on top, like a tomb. Hopefully next year it will spawn some little truffles."