Truffle (fungi)

Truffle
Scientific classification
Kingdom: Fungi Division: Ascomycota Subphylum: Pezizomycotina Class: Pezizomycetes Order: Pezizales Family: Tuberaceae Genus: Tuber
Species
Tuber aestivum Tuber brumale Tuber gibbosum Tuber himalayensis Tuber magnatum Tuber melanosporum Tuber mesentericum Tuber oregonense Tuber sinensis

A truffle (IPA: /ˈtrʌfl̩/) is the valuable and highly sought-after edible fruiting body of a group of subterranean ascomycete fungi of the genus Tuber. All truffles are ectomycorrhizal and are therefore found in close association with trees. These are the only "true" truffles, however, the term has been applied to several other genre of underground fungi around the world.

The ascoma (fruiting body) of truffles is highly prized as a food. Brillat-Savarin called the truffle "the diamond of the kitchen". Truffles are held in high esteem in French, northern Italian and Istrian cooking, as well as in international haute cuisine.

Contents 1 Etymology 2 Biology 3 Types 3.1 White truffle 3.2 Black truffle 3.3 Chinese truffles 3.4 Summer truffle 3.5 Other species 3.6 Truffle-like species 4 History 4.1 Antiquity 4.2 Islam 4.3 Middle Ages 4.4 Renaissance and modern times 5 Cultivation 6 Extraction 6.1 In New Zealand and Australia 7 Culinary use 7.1 Truffle oil 7.2 Truffle suppliers 8 References 9 External links

Etymology

The origin of the word truffle appears to be the Latin term tuber, meaning "lump", which became tufer- and gave rise to the various European terms: French Truffe, Spanish Trufa, German Trüffel, and Dutch Truffel. The German word Kartoffel ("potato") is derived from the Italian tartufo (truffle) because of superficial similarities.^[1]

Biology

The mycelia of truffles form symbiotic relationships with the roots of several tree species including beech, poplar, oak, birch, hornbeam, hazel and pine.^[2][3] They prefer argillaceous or calcareous soils which are well drained and neutral or alkaline.^[4][5] Truffles fruit throughout the year, depending on the species and can be found buried between the leaf litter and the soil.

Their growth beneath the soil surface is thought to be an adaptation to resist predation, forest fire, drought, or severe cold. Toadstools above the surface of the soil are more vulnerable to destruction.

Types

White truffle

The White truffle or Alba Truffle (Tuber magnatum) comes from the Langhe area of the Piedmont region in northern Italy and, most famously, in the countryside around the city of Alba. It is also found in Croatia, on the Istria peninsula in the Motovun forest alongside Mirna river ^[6]. Growing symbiotically with oak, hazel, poplar and beech and fruiting in autumn, they can reach 12cm diameter and 500g, though are usually much smaller. The flesh is pale cream or brown with white marbling.^[7] Like the French black truffles, Italian white truffles are very highly esteemed (illustration, right). The white truffle market in Alba is busiest in the months of October and November. The Tuber magnatum truffles sell between €2,000 and €4,000 per kilogram ($1350 - $2700 per pound). Truffle hogs have been used historically in Europe to help find truffles. However, more recently, dogs have become preferred for truffle hunting since they can be trained to just find the truffles whereas sows eat the truffles as soon as they find them.

Giancarlo Zigante and his dog Diana found one of the largest truffles in the world near Buje, Croatia. The truffle weighed 1.31 kilograms (2.9 lb) and has entered the Guinness Book of Records.

The record price paid for a single white truffle was set in December 2007, when Macau casino owner Stanley Ho paid $330,000 (£165,000) for a specimen weighing 1.5 kilograms (3.3 lb), discovered by Luciano Savini and his dog Rocco. One of the largest truffles found in decades, it was unearthed near Pisa and sold at an auction held simultaneously in Macau, Hong Kong and Florence.^[8]

The Tuber magnatum pico White truffle is mostly found in northern and central Italy, while the Tuber borchi, or Whitish truffle, is found in Tuscany, Romagna and the Marche. Neither of these is as aromatic as those from Piedmont.^[7]

Black truffle

The Black truffle or Black Périgord Truffle (Tuber melanosporum) is named after the Périgord region in France and grows exclusively with oak. Specimens can be found in late autumn and winter, reaching 7cm in diameter and weighing up to 100g. ^[7] Production is almost exclusively European, with France accounting for 45%, Spain 35%, Italy 20%, and small amounts from Slovenia and Croatia. In 1900, France produced around 1,000 metric tonnes (1,100 short tons) of Tuber melanosporum. Production has considerably diminished in the past century, and is presently around 20 metric tonnes (22 short tons) per year, with peaks at 46 metric tonnes (50 short tons) in the best years. 80% of the French production comes from south east France: upper-Provence (départements of Vaucluse and Alpes-de-Haute-Provence), part of Dauphiné (département of Drôme), and part of Languedoc (département of Gard); 20% of the production comes from south west France: Quercy (département of Lot) and Périgord. The largest truffle market in France (and probably also in the world) is at Richerenches in Vaucluse. The largest truffle market in south west France is at Lalbenque in Quercy. These markets are busiest in the month of January when the black truffles have their highest perfume. Black truffles on these markets sell between €200 and 600 per kilogram (USD$130–$380 per pound), depending on the quantity and quality of the harvest.

Chinese truffles

The Chinese truffle (Tuber sinensis, also sometimes called Tuber indicum) is a winter black truffle harvested in China. Due to their bountiful growth, Chinese truffles are often exported to the West as a substitute of inferior quality of Tuber melanosporum. Some truffle exporters or delicatessen shops sell Chinese truffles into which extracts of the real Tuber melanosporum are introduced. These truffles are often sold at a high price, marked as Tuber melanosporum.^[9] Another type of Chinese truffle is the Tuber himalayensis, which visually looks so much like the Tuber melanosporum that a microscope is needed to differentiate them. The Tuber himalayensis is harvested in very small quantities in the Chinese Himalayas due to the high altitude, and is not as frequently met on world markets as the Tuber sinensis. The third type of Chinese truffle is the Chinese summer white truffle, which does not yet have a scientific name.

Traditionally in Yunnan truffles were used as pig feed and not eaten by humans.

Summer truffle

The Black Summer Truffle (Tuber aestivum/unicinatum) thrives in northern Italy, central Europe and the UK but also grows in Turkey and North Africa. It is highly valued for its culinary uses and costs up to $1,500 per kilogram ($670 per pound). Summer truffles do not have as strong an aroma or taste as winter truffles do. They are mainly harvested from June to November . These truffles grow in symbiosis with trees such as oaks, hazels and beech. They can weigh up to 20-30 g, and their shape is generally round, up to 4 cm diameter.^[7]

Other species

Two lesser-used truffles include the Black truffle (Tuber macrosporum) and the Scorzone truffle (Tuber mesentericum). In the U.S. Pacific Northwest, several species of truffle are harvested both recreationally and commercially, most notably, the Oregon white truffles, Tuber oregonense and Tuber gibbosum.

Truffle-like species

The term "truffle" has been applied to several other genera of similar underground fungi. The genera Terfezia and Tirmania of the family Terfeziaceae are known as the “desert truffles” of Africa and the Middle East. "Hart's truffle" is a name for Elaphomycetaceae while Pisolithus tinctorius, which was historically eaten in parts of Germany is sometimes called "Bohemian truffle".^[10]

History

Antiquity

The first mention of truffles appears in the writings of Theophrastus in the fourth century BC. In classical times their origins were a mystery which challenged many; Plutarch and others thought them the result of lightning, warmth and water in the soil, while Juvenal thought thunder and rain to be instrumental in their origin. Cicero deemed them children of the earth, while Dioscorides thought they were tuberous roots.^[10]

Italy in the Classical Period produced two kinds of truffles: the Tuber melanosporum and the Tuber magnatum. The Romans, however, only used the terfez (Terfezia bouderi), a fungus of similar appearance which the Romans called truffles, and which is sometimes called "desert truffle". Terfez used in Rome came from Lesbos, Carthage, and especially Libya, where the coastal climate was less dry in ancient times.^[10] Their substance is pale, tinged with rose. Unlike truffles, terfez have no taste of their own. The Romans used the terfez as a carrier of flavour, because the terfez have the property to absorb surrounding flavours. Indeed, Roman cuisine used many spices and flavours, and terfez were perfect in that context.

Islam

It is narrated in the hadith Sahih Muslim that Islamic prophet Muhammad said "Truffles are 'Manna' which Allah, sent to the people of Israel through [Moses], and its juice is a medicine for the eyes."^[11] Terfezia was the main truffle consumed in the Middle East historically, and Ludovico di Varthema, in his Travels (1503-08), wrote of great quantities of them being sold, having been harvested in the mountains of Armenia and Turkey.

Middle Ages

Truffles were rarely used during the Middle Ages. The only trace of truffles in medieval cooking is at the court of the Avignon Papacy. The popes discovered them when they relocated to Avignon, near the producing regions of upper Provence, and they became very fond of them. Truffle hunting is mentioned by Bartolomeo Platina, the papal historian, in 1481, when he recorded that the sows of Notza were without equal in hunting truffles, however they should be muzzled to prevent them from eating the prize.^[12]

Renaissance and modern times

During the Renaissance truffles regained popularity in Europe and were honoured at the court of King Francis I of France. However, it was not until the 17th century that Western (and in particular French) cuisine abandoned "heavy" oriental spices, and rediscovered the natural flavour of foodstuffs. Truffles were very popular in Parisian markets in the 1780s. They were imported seasonally from truffle grounds, where peasants had long enjoyed their secret. Brillat-Savarin (1825) noted characteristically that they were so expensive they appeared only at the dinner tables of great nobles and kept women. A great delicacy was a truffled turkey. "I have wept three times in my life," Rossini admitted. "Once when my first opera failed. Once again, the first time I heard Paganini play the violin. And once when a truffled turkey fell overboard at a boating picnic."

Cultivation

Truffles long eluded techniques of domestication, as Jean-Anthelme Brillat-Savarin (1825) noted with his characteristic skepticism:

"The most learned men have sought to ascertain the secret, and fancied they discovered the seed. Their promises, however, were vain, and no planting was ever followed by a harvest. This perhaps is all right, for as one of the great values of truffles is their dearness, perhaps they would be less highly esteemed if they were cheaper.

"Rejoice, my friend," said I, "a superb lace is about to be manufactured at a very low price."

"Ah!" replied she, "think you, if it be cheap, that any one would wear it?"

However, contrary to stubborn legends, truffles can be cultivated. As early as 1808, there were successful attempts to cultivate truffles, known in French as trufficulture. People had long observed that truffles were growing among the roots of certain trees, and in 1808, Joseph Talon, from Apt (département of Vaucluse) in southern France, had the idea to sow some acorns collected at the foot of oak trees known to host truffles in their root system.

The experiment was successful: years later, truffles were found in the soil around the newly grown oak trees. In 1847, Auguste Rousseau of Carpentras (in Vaucluse) planted 7 hectares (17 acres) of oak trees (again from acorns found on the soil around truffle-producing oak trees), and he subsequently obtained large harvests of truffles. He received a prize at the 1855 World's Fair in Paris. These successful attempts were met with enthusiasm in southern France, which possessed the sweet limestone soils and dry hot weather that truffles need to grow. In the late 19th century, an epidemic of phylloxera destroyed much of the vineyards in southern France. Another epidemic destroyed most of the silkworms in southern France, making the fields of mulberry trees useless. Thus, large tracts of land were set free for the cultivation of truffles. Thousands of truffle-producing trees were planted, and production reached peaks of hundreds of tonnes at the end of the 19th century. In 1890 there were 750 km² (185,000 acres) of truffle-producing trees.

In the 20th century however, with the growing industrialization of France and the subsequent rural exodus, many of these truffle fields (champs truffiers or truffières) returned to wilderness. The First World War also dealt a serious blow to the French countryside, killing 20% or more of the male working force. As a consequence of these events, newly acquired techniques of trufficulture were lost. Also, between the two world wars, the truffle fields planted in the 19th century stopped being productive. (The average life cycle of a truffle-producing tree is 30 years.) Consequently, after 1945 the production of truffles plummeted, and the prices have risen dramatically. In 1900 truffles were used by most people, and on many occasions. Today, they are a rare delicacy reserved for the rich, or used on very special occasions.

In the last 30 years, new attempts for mass production of truffles have been started. Eighty percent of the truffles now produced in France come from specially planted truffle-fields. Nonetheless, production has yet to recover its 1900s peaks. Local farmers are opposed to a return of mass production, which would decrease the price of truffles. It is estimated that the world market could absorb 50 times more truffles than France currently produces. There are now truffle-growing areas in the United States, Spain, Sweden, New Zealand, Australia, and the UK.

In 1992, Franklin Garland from Hillsborough, North Carolina became the first person to successfully cultivate the Black Périgord Truffle (Tuber melanosporum) in the New World. He has subsequently started a truffle tree nursery, Garland Gourmet Mushrooms and Truffles, which has supplied over 300,000 trees across the United States. There has been successful production across the mid-Atlantic states: in NC, from Raleigh west to the Asheville area; In Virginia, in the band of land between Highway 95 and Highway 77. Western Tennessee has also proven successful and orchards are currently being planted in the Louisville KY area. The Pacific northwest has several orchards planted, but none of them have yielded these truffles to date.

Extraction

Looking for truffles in open ground is almost always carried out with specially trained pigs (truffle hogs) or, more recently, dogs. Pigs were the most used in the past, but recently dogs are preferred.

Truffle Hog	Truffle Dog
Keen sense of smell	Keen sense of smell
Innate ability to sniff out truffles	Must be trained
Tendency to eat truffles once found	Easier to control; may urinate on truffles

The female pig's natural truffle seeking as well as her usual intent to eat the truffle is due to a compound within the truffle similar to androstenol, the sex pheromone of boar saliva, to which the sow is keenly attracted.

In New Zealand and Australia

The first black truffles (Tuber melanosporum) to be produced in the southern hemisphere were harvested in Gisborne, New Zealand in 1993. In 1999, the first Australian truffles were harvested in Tasmania, the result of eight years of work. Trees were inoculated with the truffle fungus in the hope of creating a local truffle industry. Their success and the value of the resulting truffles has encouraged a small industry to develop. A Western Australian venture had its first harvest in 2004, and in 2005 they unearthed a 1 kg truffle that is potentially the largest ever harvested in the southern hemisphere. Production is expanding into the colder regions of Victoria and New South Wales.

Culinary use

Because of their high price and their pungent taste, truffles are used sparingly. Supplies can be found commercially as unadulterated fresh produce or preserved, typically in a light brine.

White truffles are generally served raw, and shaved over steaming buttered pasta or salads. White or black paper-thin truffle slices may be inserted into meats, under the skins of roasted fowl, in foie gras preparations, in pâtés, or in stuffings. Some specialty cheeses contain truffles as well.

The flavour of black truffles is far less pungent and more refined than that of white truffles. It is reminiscent of fresh earth and mushrooms, and when fresh, their scent fills a room almost instantly. In 2006, designer Tom Ford released a perfume that lists black truffle as its first note.^[13]

While in the past chefs used to peel truffles, in modern times most restaurants brush the truffle carefully and shave it or dice it with the skin on so as to use most of this expensive ingredient. A few restaurants, such as Philippe Rochat in Switzerland, still stamp out circular discs of truffle flesh and use the skins for sauces.

Truffle oil

Main article: Truffle oil

Truffle oil is often used as a lower cost and convenient substitute for truffles, to provide flavouring or to enhance the flavour and aroma of truffles in cooking. Most of the “truffle oil” used in the US however, does not contain any truffles.^[14] The vast majority is olive oil which has been artificially flavoured using a synthetic agent such as 2,4-dithiapentane. Daniel Patterson reported in the New York Times that "even now, you will find chefs who are surprised to hear that truffle oil does not actually come from real truffles." Many chefs continue to use inexpensive synthetic truffle oil, considering it to be "a reasonable substitute."

Truffle suppliers

Truffles have become not just a luxury food for the restaurant industry, but a food that anyone can enjoy, therefore online truffle suppliers have started to be found throughout the U.S. for their truffles, truffle products and other specialty foods.
Zigante tartufi, a company from Croatia is the number one exporter of truffles to the U.S.

References

External links

• "In the throes of truffle fever" by Tyrone Beason, Seattle Times, January 4, 2007.
• Various Truffle storage methods, preparations, and recipes.
• Sorting truffle names
• Photos from Truffle Festivals in Piedmont and Tuscany
• The Trifolau - Hunting Truffles in Tuscany