Wild About Mushrooms: Truffles
Truffles
Tuber aestivum, T. gibbosum, T. magnatum, T. melanosporum, T. texensis
Truffles have been found in Europe, Asia, North Africa, and  North America, but only three species are commercially important.  They live in close mycorrhizal association with the roots of specific  trees. Their fruiting bodies grow underground.
The term "truffle" as commonly used refers to members of  the genera Tuber and Terfezia. There are many other kinds of  subterranean fungi, "false truffles," which outwardly resemble the  ones we eat. They are far more common than the ones that are  collected for food, and some are poisonous.
Truffles are round, warty, and irregular in shape and vary  from the size of a walnut to that of a man's fist. The season for  most truffles falls between September and May.
The mention of truffles conjures up images of the expensive  French black truffle (Tuber melanosporum) from the Périgord region  of southwest France, used in making p�t� de foie gras, or the  renowned odorous white truffle (Tuber magnatum) of Alba, in the  Piedmont district of Italy.
Since the times of the Greeks and Romans these fungi have  been used in Europe as delicacies, as aphrodisiacs, and as medicines.  They are among the most expensive of the world's natural foods, often  commanding as much as $250 to $450 per pound.
Truffles are harvested in Europe with the aid of female pigs  or truffle dogs, which are able to detect the strong smell of mature  truffles underneath the surface of the ground. The female pig becomes  excited when she sniffs a chemical that is similar to the male swine  sex attractant. The use of pigs is risky, though, because of their  natural tendency to eat any remotely edible thing. For this reason,  dogs have been trained to dig into the ground wherever they find  these odors, and they willingly exchange their truffle for a piece of  bread and a pat on the head. Not a bad trade for the truffle hunter!  Some truffle merchants dig for their prizes themselves when they see  truffle flies hovering around the base of a tree. Once discovered,  truffles can be collected in subsequent years at the same site.
The flavor of the truffle is directly related to its aroma.  The chemicals necessary for the odor to develop are created only  after the spores are mature enough for release, so they must be  collected at the proper time or they will have little taste. This is  the only sure indication that the mushrooms are ready to be  harvested. That is why animals have proven to be the best means of  assuring that the fungi collected will be flavorful.
Although commercial truffles are more plentiful in Europe than  in America, fewer are found there now than in the past. A harvest of  2,200 tons was reported in l890. Three hundred tons were harvested  in l914, but lately only 25 to 150 tons per year have been found.  Truffles appear to have predictable life cycles. To ensure future  production, appropriate tree seedlings are inoculated with truffle  spores, and when the sapling tree is established, it is transplanted  to the proper environment, usually a barren, rock-strewn calcific  soil. It takes about seven years before the first truffle begins to  grow. A bearing tree will produce for about fifteen to thirty years.  For the European market to survive it is necessary to regularly  replenish the population of truffle-bearing trees. Inoculated trees  have been brought to North America, but it is too early to predict  how successful these experiments will be.
Truffles are also found in North Africa, in the Middle East, and  in North America. On the desert after rainfall, knowledgeable Middle  Eastern people collect the "black kame," Terfezia bouderi, and the  "brown kame," Terfezia claveryi. They prefer the darker ones. In  Texas, Tuber texensis is collected, and in Oregon, the white Tuber  gibbosum.
Gaining in popularity and comparing favorably with the Italian truffle, the Oregon truffle is harvested in sufficient quantity to support  commercial sales. Although the Oregon truffle industry is in its  infancy, it commands as much as $150 per pound for its truffles.  James Beard claimed that the mature Oregon white truffle could be  substituted for European varieties.
Originally found in California, the Oregon truffle grows in  association with Douglas fir trees and is a major food source for  many small rodents and other mammals. These underground fungi depend  on animals to remove them from below the surface of the earth and to  disperse the spores that result in the continuation of their species.  Here is an example of complex ecology in which the tree, the fungus,  and the animal depend on each other.
Collecting truffles requires training and experience. A  small hand rake or cultivator is used to gently uncover the soil near  the base of suspected host plants. As a rule, in the Northwest,  these hosts are various kinds of conifer trees. Small freshly made  holes at the bases of trees, which are not part of animal tunnels,  are excellent indicators that animals have been digging for fungi.
To enjoy the wonderfulness of the variously described  pleasure of dining on truffles, you must eat fresh, uncooked  specimens shortly after they have been harvested. The strength of the  truffle flavor decreases rapidly with time, and much of it is lost  before some truffles reach the market. However, lovers of these  earthly gems advise us that freshly harvested truffles can be  purchased in advance from some local specialty stores. Wholesalers  cover them with rice on restaurant serving trays in a refrigerated  room as soon as they arrive via overnight air freight. The next day  they are delivered to the store where your order was placed. When  you spend as much money as will be needed for such culinary  experiments, try to assure that you get truly fresh truffles.
The Italian white truffle is considered to be superior in smell  and taste to the French black truffle. What does a truffle smell  like? "A combination of musk, nuts, and ozone," was one observer's  description. T. aestivum, a black summer truffle found in Germany,  smelled to one observer like "a freshly opened can of creamed corn."  This black variety is not considered as choice as the other two  European truffles. In Italy one Ping-Pong ball-sized Italian truffle  has been said to have perfumed an entire apartment. The powerful  pungency of this small tuber was such that some of the inhabitants  were forced to flee!
Cleaning
Remove any soil from truffles just before eating. They must be  washed with water and brushed. The outside must be immaculate since  they will be used unpeeled. Dry with a paper towel.
Cooking
The fungus is scraped or grated onto food and into sauces  and soups just before eating. Truffle slicers have been especially  designed for this purpose. Experts recommend that veal, chicken, fish,  souffl�s, omelettes, pasta, and rice can be glorified with thinly sliced  truffles. Cream and cheese sauces avidly take up their flavor.
Insert thin wedges of truffle under the skin of a chicken and  store it overnight in the refrigerator before roasting.
A well-known chef prepares a high-quality p�t� de foie gras  baked with a stainless steel tube running through the center. As  soon as the p�t� is cooked, he fills the tube with diced uncooked  truffles and then removes the tube.
T. magnatum, the most aromatic of the truffles, is crushed in  olive oil in Italy, filtered, and dispensed in 3-ounce medicine  bottles with eye droppers. Some suspect that the crushed truffles  are then packed in cans for sale in foreign markets. Call local cooking schools or specialty  shops to locate this juice. Only a few drops are needed to  strengthen the flavor of prepared truffles.
Preserving
The pungent odor of a truffle will penetrate the shells of eggs  and flavor kernels of rice when stored with them in a closed glass  jar placed in a refrigerator. Once the prize truffle has been  consumed, the eggs may be enjoyed in an omelette and the rice in  pilaf.
Truffles can be frozen for two weeks in a freezer-proof glass  jar. Another recommendation is to store them whole in bland oil.
Truffle Butter
The aroma and flavor of truffles are heat sensitive. Truffle butter  is a good way to get the most from your aromatic gem since it is not  heated.
Finely grate a fresh truffle and add to softened unsalted  butter in proportions to suit your taste. Use enough butter so that  the mixture is spreadable and not crumbly. Let stand at room  temperature for an hour. Spread on crackers, French bread, or baked  potatoes. Truffle butter freezes well.
--Anne B. Marin
Truffled Eggs
Henry and Wanda are members of the North American Truffling Society  in Oregon that is devoted to the collection and study of truffles.  Members have made generous contributions to this book.
Cut an egg carton in half crosswise. Place 1 or 2 (preferably  2) medium truffles in each carton in the middle of the eggs. Enclose  the cartons in a plastic bag and seal. Place in the refrigerator.  The eggs will be ready for use after 3 days. (Do not keep the eggs in  the refrigerator longer than 1 week, as their odor and flavor may  become too strong, and the lack of fresh air may cause them to  spoil.) The eggs may be used to prepare scrambled eggs, omelettes, or  your favorite deviled egg recipe.
--Henry J. and Wanda A. Pavelek
Truffle Pâté
This recipe was developed for the Oregon white truffle, but other  truffles can be substituted.
1 to 2 ounces truffles
1 cup beef broth
1 apple, peeled, cored, and chopped
2 tablespoons shallots or green onions, minced
1/4 cup fresh lemon juice
1/4 cup cold water
2 envelopes (2 tablespoons) plain gelatin
1 cup (2 sticks) butter, cut into pieces
2 tablespoons Triple Sec
Dash of dry mustard
Ground pepper to taste
Clean the truffles with a soft brush. Dice large specimens to  1/4 inch and split small truffles to release the flavor. In a  saucepan, bring the beef broth to a boil, then simmer the truffles  for 20 seconds. Pour the broth through a sieve into a bowl and set  the truffle pieces and the broth aside.
Oil a 5-cup mold or enough small crocks to hold 5 cups. Combine  the livers, onion, apple, reserved broth, and shallots in a medium  saucepan and bring to a boil over medium heat. Reduce the heat,  cover, and simmer for 5 minutes. Blend the lemon juice, water, and  gelatin in a small bowl, stirring well until the gelatin dissolves.  Pour into the liver mixture and mix thoroughly. Remove from the heat  and add the butter a little at a time, blending well after each  addition. Stir in the remaining ingredients. Let cool 15 minutes.
Transfer the mixture to a blender or a food processor and puree  until nearly smooth. Let stand 10 minutes. Pour into a mold or  crock, layering in about 3 layers of truffle pieces. Cover and chill  overnight. Even better, allow 24 to 48 hours to develop the truffle  flavor in the p�t�.
--Frank and Karen Evans