There's a very good reason why, says Dr George Dodd, director of olfactory research at Warwick University. Truffles belong to one of seven families of pheromones, those human body odours by which we establish our sexual compatibility. Six other categories are also found in foods, he says; in caviar, shellfish, ripe cheese, champagne, vintage wine and beer.
But surely there must be cheaper ways of getting a thrill. To buy the fabled white truffle of Piedmont at the height of its season (now), you must pay pounds l,200 per kilo. A pheromonal price.
The white truffle is marginally more expensive than the dearest rival, Iranian beluga, (importer WG Whyte sells it at pounds 965 per kg). The black truffle from Perigord, in France, (pounds 800 to pounds l,000 for a kilogram) is next.
It is the perceived intensity of perfume which accounts for the price difference between the white truffle Tuber magnatum and the black truffle Tuber melanosporum. The white variety has the more pronounced aroma, though perhaps not a lot of taste. And what little there is will be virtually lost in cooking.
The black truffle's smell is less pronounced, yet, magically, it transfers its character to food preparations when it is cooked, most notably in truffled foie gras, or impregnating a fowl such as a capon or turkey.
Ask not who can afford Piedmontese white truffles. That engaging caricature of an Italian, television cook Antonio Carluccio, was first to put them on the menu, in his Neal Street Restaurant. (This year he has put together a mail-order mini-truffle basket; see details overleaf).
But these days he's far from alone. The brief season of the Italian white truffle (November to January) is celebrated in all up-market London Italian restaurants. And there is no shortage of customers prepared to dig deep into their pockets for a sniff of its magical perfume, eating it flaked on to a warm salad, or over a baked vegetable in a cheese sauce, or with baked eggs in cream.
A risotto with a dusting of fine flakes of white truffle starts at pounds 30 at The Halkin, Belgravia's famous Michelin-starred Italian table. Chef Stefano Cavellino says you'd get a generous portion of 10g grated on top. Larger helpings are offered but, unless your bank allows bottomless credit, you need to know when to say "when".
The white truffle is a winter jewel in the crown of the River Cafe's cooking, a Hammersmith restaurant described by the New Yorker this year as "Best Italian Restaurant in Europe". In fact, its polenta with white truffles is a dish to be included in an alternative Christmas dinner menu prepared by owner-cooks Ruth Rogers and Rosie Gray for a BBC2 television special, to be shown in the week beginning 14 December.
Some alternative Christmas dinner, huh, with truffles at pounds l,200 per kilogram? You wouldn't need a whole kilo but, anyway, those amongst us less fortunate can still a get a truffle fix of sorts. Most modern British chefs sport a bottle of truffle oil on their shelves, and a judicious addition to many a savoury dish transforms it; dribbled into a soup, applied to a salad of warm pigeon breasts or combined with cultivated and wild mushrooms.
You can buy little phials of white truffle oil (pounds l0 for 40ml) or black (around pounds 5 for 55ml), or at about pounds 25 for a larger bottle (325ml), in most delicatessens. Many of them now sell an increasing range of truffled things; jars of dry polenta with truffles and porcini, jars of truffled risotto rice, truffled butter, truffled mustard. Even Tesco is on the case, offering truffle oils and truffle butter.
Time, is it not, to see where all these truffles are coming from, with Anna del Conte as my guide, author of Food of Northern Italy (Pavilion pounds 16.99). Over to a sun-dappled, hilly wood near Asti, northern Italy, where we are guests of Carlo Ercole, head of the famous Sacla company.
Although it exports millions of jars of pesto and sundried tomatoes, what it has agreed to show us is a unique, top secret and very exclusive product: anchovies bottled with truffles. In a top shop a small jar would sell at pounds 30 or more, but in fact sales are non-existent, for the modest number of 350 jars prepared each year are for giving away.
It will not be enough to observe the process; we will be up at first light to witness trading in the Piazza del Statuto. Here is the original car-boot sale, unostentatious cars parked around the side streets, 30 or 40 men huddling in groups, breaking off to make a secretive deal with one of the agents. Our guide is Dario Pastrone, as renowned as a truffle- hunter in the region as, say, a local bullfighter might be in Spain. At his bidding, little parcels are unwrapped to reveal to us the treasure trove inside. It is no more appealing than a handful of lumpy little potatoes, with skins of clay.
So that they do not lose moisture they are put in cheap plastic boxes, wrapped in assorted old cloths, woolly cardigans, dusty tissues and, in one instance, the sports pages of La Nuova Provincia.
Dario tells us that there are 8,000 truffle hunters between here and Alba. Most will have other sources of income. Dario is an engineer with the electricity board and he saves his annual holidays for the truffle season.
He is going to take us on a foray into the woods.
Truffles are members of the fungus family and attach themselves to the roots of certain trees, fam-ously the oak, but also hazel, willow, plane, poplar. Their manner of growth still defeats agronomists though they have planted forests of oaks (in Spain and New Zealand) and miles of hazelnuts (in Italy) in their search, producing some truffles, it's true, but failing so far to find the Holy Grail of true perfume.
Most truffle hunting is done at night, partly because the dogs who sniff them out need the minimum of distraction (from noise and smells), and partly because hunters wish to conceal from prying eyes the specific trees which are known hosts to the truffle. But to accommodate us, Dario will take us out in the morning.
When we meet him again, he is waiting on the wrong side of the highway, the first of a series of false tracks. He introduces us to Cita, his eight-year-old truffle dog, a wee thing, a batardina, or mongrel bitch. It takes two years to train a dog and it then has about five years' hunting in it. They can change hands for pounds l,000 to pounds 4,000.
Dario knows a man whose truffle dog is so old, the owner spares its energies by carrying it through the woods, releasing it only at likely sites. A few pigs are still used, their sense of smell being the keener, but it's difficult to stop them eating the truffles, says Dario. They are also heavy to carry around when they get old.
We're off. Clutching a short-handled hoe and forked hazel stick, Dario leads us up a hill to a farmer's vegetable patch, then ducks behind a line of trees to enter a sloping wood. Here, the soil provides the essential drainage the truffles need.
"Duma, duma," calls Dario, addressing Cita in the local dialect (duma for andiamo, let's go!). "Bugia! (move it) Pian! (shshsh)." And a lot more, probably along the lines of "Cita, don't you remember where we planted it earlier." Cita remembers and, sniffing urgently, brushes aside some dead leaves. "Pila! (dig)" orders Dario, and she then scratches away at the covering of soil. "Ferma! (stop)" says Dario.
Dario removes Cita's snuffling nose, uncovering a small clay-coloured lump rather larger than a golf ball. He exchanges the 100g prize worth 250,000 lire (pounds 100) for a dog biscuit worth two lire.
Cita is overjoyed, her loyal eyes shining with pleasure. "She's more concerned about pleasing her master than finding a truffle," observes one of our party. Unexpectedly, Cita excels herself, finding two more very little ones, "piccolini", in a site Dario evidently felt was spent.
Although truffles are growing all year among the roots of various host trees, there is only a period of 20 days when they give off perfume to a degree which (putting on our David Attenbor-ough hats) attracts hunters who will dig them up and spread their spores to ensure further reproduction. So far, then, the human predator is the one who can't crack it. There were many more truffles in the days when wild boars roamed the forests, says Dario, who was once chased up a tree by a particularly well-horned male.
We've seen enough. The proof of the pudding is in the eating and we repair to Gener Neuv, Asti's most elegant restaurant. It shows no sign of the damage incurred two years ago when the River Tanaro overflowed its banks and completely submerged it. The owner, Piero Fassi, has weighed out some 300g of white truffles on his scales, pounds 300 worth, and we join a party of 10 intent upon reducing the pile to nothing.
What is it that's magical about the aroma of the Piedmont truffle, I ask them in turn. The sow, seeking them out, recognises the smell of her mate on heat, does she not? No one, in mixed company anyway, is prepared to share thoughts about human sexual chemistry. So, what is that aroma? The smell of ripe cheese, and a touch of garlic, offers Anna del Conte.
Signor Fassi produces his truffle slicer, and with wristwork worthy of Pete Sampras, slices a snow of truffle flakes onto a succession of dishes; a pate of chicken, a bowl of buttered tagliolini, a dish of baked polenta with an egg buried in it with a fonduta of Fontina cheese poured on top.
Mashed potatoes ought to be good with truffles, I thought, as I shamelessly indulged myself. Certainly anchovies are. Anchovies, olives and olive oil from Liguria have been the fruits of trading the wines of Piedmont from earliest times. An anchovy, not a wooden spoon, is the prize for coming last in the Palio (the annual horse race around the square; a palio, or flag, is the prize for winning). And a regional dish here is bagna calda (literally a "hot bath"), a bowl of hot, garlicky anchovy sauce for dipping crisp vegetables into.
So, finally, to the most unique of the regional truffle specialities, anchovies with truffles.
In the Sacla laboratory, five ladies in white coats are patiently cleaning salted anchovies from a 10kg can (the plump ones from Spain). With the backs of knives they scrape off the silvery scales, trim away small bones, even picking out some bones, much finer than the thickness of human hair. It's slow work, and they rub the bits away with paper towels. It will not do to wash them. The trimmed reddish-brown fillets are marinated in a tray of olive oil for two hours. Then they are drained and patiently inserted, one by one, into jars, a finely-sliced circle of truffle prodded behind each one, a process taking some five or 10 minutes each jar. Fine- tuned scales measure each portion of sliced truffle, at precisely 7g.
This is actually something you could do at home, buying salted anchovies from a delicatessen, cleaning them carefully. An investment of pounds 7 in a small white truffle is a modest one when you think of the 30-odd anchovies that later could be chopped onto 30 slices of bruschetta. You can thus confer a luxurious touch to many a slice of toasted country bread, served along with a few other choice Italian bits and pieces.
1 whole fresh free range egg
butter or truffle oil
a ramekin large enough for one egg and the equivalent cream
15g or a few shavings of truffle
salt and pepper to taste
Oil the ramekin liberally (the oil will give the dish more taste). Break the egg into the ramekin, add enough cream to cover the egg and put in a very hot oven for a few minutes.
The egg white should be solid, and the yolk runny. Take out, add salt and pepper to taste and a few shavings of truffle. Serve together with toasted fingers of country bread.
This warm anchovy and garlic dip for raw or cold, cooked vegetables is a traditional dish which goes back as far as the 16th century and is associated with feast days. Our host Carlo Ercole prepared this for us, using 20 cloves of garlic, but modifying their fierce taste by first simmering them gently in milk for 30 minutes. This is the recipe of my co-guest Anna del Conte.
4 garlic cloves, peeled and very finely sliced
5 salted anchovies, rinsed and boned, or 10 anchovy fillets
200ml/7fl oz olive oil
1 white truffle (optional)
Melt the butter in a small, deep earthenware pot or a very heavy-based saucepan over the lowest heat. As soon as the butter has melted, add the garlic and saute for just a few seconds. The garlic should not colour.
Add the anchovies to the pot and pour the oil in very gradually, stirring the whole time. Cook for about 10 minutes, always on the lowest possible heat and stirring constantly.
The dip is ready when the ingredients are well blended and smooth. Add slivers of the truffle and serve the bagna calda.
Bagna calda should be kept hot in the same way as a fondue, over a spirit lamp or a candle placed in the middle of the table.
! Truffle baskets from Antonio Carluccio. A 35g jar of two black summer truffles in brine, a small bottle of white truffle oil (55ml), a truffle grater and an 80g jar of mushroom and truffle sauce costs pounds 39. Telephone Carluccio's on 0171 240 5710.
Harvey Nichols, Fortnum and Mason and Harrods have both white and black (winter) truffles in jars. The black summer truffle is the cheapest, having the least flavour. Most expensive are whole, brushed truffles, then pieces and, finally, the so-called peelings.
Many delicatessens have truffled products, at a price. For example, Mortimer & Bennett in Turnham Green, London (0181 995 4145) sells polenta with porcini,mushrooms and truffles (180g for pounds 8.50), a risotto mix with porcini and truffles (200g for pounds 10.50), white truffle oil (40ml for pounds 8.95), jars of black and white truffles, truffle paste, truffled mustard and, rather oddly, greengages in truffle oil.Reuse content