truffe (French), Trüffel (German), tartufo (Italian), trufa (Spanish)
(Tuber sp. and Leucangium carthusianum) There are about 2,000 truffles and truffle-like fungi that are known. True truffles, though, are confined to members of the Tuber genus, of which there are about 100 species. Truffles are the culinary superstars of the mushroom world, commanding fantastic prices and regarded as one of the finer luxuries in life. The Perigord region of France and the Italian Piedmont are acknowledged as the home of the finest. However, they do grow all over the world. The tuber grows underground and usually found as a result of its distinctive aroma. The scent is fairly close to that of the male sex pheromone for pigs, which explains why pigs are so easily trained to find them. Other animals are also able to find them. When they are ripe, they give off an aroma that is highly stimulating to certain forest creatures. In some places, it is the common fly that will swarm near the base of a tree, alerting truffle hunters where to dig.
Since truffles are highly aromatic and potent, a little goes a long way. The truffle is normally shaved into paper-thin slices using a special mandoline. Older truffles lose their scent quickly. Fresh truffles can be stored for a couple of weeks if they are wrapped in paper towels, sealed in a covered container, and refrigerated. The best way to store fresh truffles is to clean them well and place them into a glass jar topped off with olive oil. The aromatic components are trapped by the oil, infusing it with a wonderful truffle flavour. The oil does have to be refrigerated and used within a month. Truffle paste and oil made from truffle trimmings are cheaper ways to experience the truffle flavour, but use these items sparingly as their pungent flavour will quickly overpower a dish. Also be aware that some commercial truffle oils are made from artificial flavours. Therefore, the more expensive oils are often worth the extra price. There are many other truffles that are unusual, undiscovered, or have limited culinary uses. Many are favoured by deer, rabbits, and other forest creatures. The European truffles fruit in hardwood forests. In the Pacific Northwest, they appear in a mix of forest from strands of Garry oak to old-growth rainforests.
Black (perigord) truffle (Tuber melanosporum) is a famous product of the broad oak forests of central and southern France, and is a gastronomic delight that has inspired chefs for centuries. A true black truffle can cost in excess of $1,000 per pound and remains one of the most expensive food products around. Trained pigs and dogs are used to sniff them out, and it is not unheard of to have these animals stolen. The perigord truffle has a blue-black exterior when fresh, but fading to brown-black with age. Commercial growers are now developing truffle-inoculated trees. Several closely related species are also edible.
Chinese and Himalayan truffles (Tuber sinense, T. indicum, and T. himalayense) are three distinct species found in South China, but pickers tend to lump them together as Chinese truffles. This is unfortunate since the flavour and quality vary from one species to another. First marketed in France in 1994, these truffles are now found in American restaurants at fairly reasonable prices, but their flavour and aroma do not come close to that of the French truffles. T. indicum is recognizable by its rich brown meat and very fine white veins. Looking like a piece of chocolate, the taste soon brings one back to reality. T. sinense also looks richly dark with large ivory veins and is moist and chewy, oily with a bitter aftertaste; but it keeps well if nothing else.
Indian White truffle or Alba (Tuber magnatum) is considered second best to the black ones, but its cost is still prohibitive because of its rarity. It is native to the foothills and mountains of northern and central Italy. In Istria, Croatia, it is considered the finest and most aromatic of truffles. The tubers grow in conjuction with oak, hazel, poplar, and beech trees. The current market price for white truffles can be double the rate for perigord truffles, which is partly because of the success in cultivating the perigord truffle. The flesh is solid, light-coloured, and very brittle; and it is not unheard of for a fresh truffle to shatter if dropped on the floor. Large specimens can weigh as much as a pound, but most are the size of large walnuts. The white truffle is slightly more perishable than its darker cousins, and the flavour and aroma diminishes within a week or two after harvest. The white truffle has a distinctive pepper edge and is often eaten raw. The skin is a dirty beige when fresh, turning a darker brown with age.
Oregon White truffle (Tuber gibbosum) looks like the Italian white truffle, but has no other similarities. It has recently been found in Oregon and along the Pacific coast; and, although of good quality, it does not compare with Piedmont truffles. Therefore, the cost is easier to handle. These truffles are associated with mature stands of Douglas fir, and have been found all along the slopes of coastal mountain ranges. The best ones have a spicy sweet, musky, cedary odour, with hints of cinnamon, nutmeg, and vanilla.
Oregon Black truffle (Leucangium carthusianum, formerly Picoa carthusiana) is the only truffle in this group that is not a Tuber species. This classification is an oddity as it may have more of the black truffle aroma than do other true truffles. Some equate the aroma to a strange mix of pineapple, port, mushrooms, rich soil, and chocolate. Looking like irregular lumps of coal, with white-veined flesh, the Oregon black truffle has a texture of moist Parmesan and ground almonds. Those that are best are very hard and dry with no signs of sponginess. Large ones have obviously spent more time in the ground and, therefore, at a greater risk of being nibbled by wildlife. Avoid any with an ammonia scent for sure, because not only have the wildlife nibbled, but they have watered it as well.
Summer truffle (Tuber aestivum) has a relatively light perfume, but mimics the black truffle with its black exterior and its off-white interior. Despite its blander flavour, the popularity of the summer truffle is increasing. Native to France, Italy, and Spain, the summer truffles are usually at their best in July, but can be found from May to October. Avoid any that look parched, as their flavour will be as well. In this case, bigger is better since large slices provide more crunch, which is the special trait of this truffle.
Tuscan truffle, spring truffle, bianchetto (Tuber borchii, formerly T. albidum) is similar to the white truffle in appearance but not in flavour; but others are different, having a chestnut to very muddy tan with a softish interior equally divided between chocolate brown and white. The flavour can be distinctly garlicy, while others are reminiscent of petroleum or gasoline.