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Spanish Black Truffle

Earthy Aromas

Pickers use trained dogs to find truffles. Juan Manuel Sanz/©ICEX

Author: Jorge L. Bartolomé/©ICEX

"The black truffle is the soul of nature, its hidden essence". It was a categorical statement from Spanish chef Santi Santamaría. But before it reached the world's top kitchens, this delicacy had to travel through time and space, from the depths of the earth to the table, in a mist of darkness and magic.

The oldest texts known to man were found many centuries ago in Mesopotamia, engraved on clay. The Sumerian society of the time knew of the fruit that grew underground without being sown and that went on to become one of the favorite foods of kings. It was a fungus belonging to the tuberaceous species, genus Tuber, a truffle.

We now know, centuries later, that the Ancient Egyptians were very fond of truffles. Several chronicles report that the Pharaoh Cheops liked to eat them coated in goose fat and cooked en papillote. The Jewish people also revered truffles. The story of their discovery of manna, a gift from God to his people, is described in the book of Exodus and, according to some interpretations, manna might have been a sort of truffle. And the Greeks and Romans, from Pythagoras to Pliny and Cicero, sang the praises of this fungus that featured on the tables of Roman Emperors and senators.

With the Renaissance, the truffle started to appear in the European courts. The French gastronome and writer Jean-Anthelme Brillat-Savarin paid tribute to it in his Physiology of Taste, with one of the most famous sentences with regards to the truffle, calling it "the black diamond of gastronomy". That was in 1825. Since then the truffle has never ceased to grow in popularity and its qualities have been admired by all lovers of good food.

Asleep among the Roots

The black truffle, or Tuber melanosporum, is an underground fungus with a similar origin to that of the white Piamonte truffle (Tuber magnatum) and other truffles offering less quality and aroma, such as Tuber brumale and Tuber aestivum, the summer truffle. The shape is more or less spherical, and the surface is rough, with small pyramid-like lumps. It needs such special growing conditions that it is only found in the Mediterranean Basin countries. Spain, together with Italy and France, is one of the main producer countries.

The black truffle can only develop in symbiosis with the roots of certain quercus trees, especially holm oaks, hazelnut and oaks. But it also needs the right climate and a precise geographical location.

We start out in the depths of winter in a field of holm oaks. Snuggled up against the roots of a tree is a black truffle, one that must release its spores and begin its reproduction. So nature performs another of its tricks. The dense, pungent, unique aroma of the truffle attracts animals with a well-developed sense of smell, such as wild boars, badgers, foxes and even insects that seek out the truffle as food. They then propagate the spores, helping them reach the roots of other trees that can cradle the development of further truffles.

Then comes spring. By this time the spore has found its place amongst the roots of the new tree, forming the mycorrhiza. During May and June, the truffle starts to form but will only do so if it receives plenty of moisture during the summer. This is one of the most delicate stages of development. Without rain, the fungus will not grow and will remain hidden forever; however, with rain, in August and September it will swell and reach the last phase of its life cycle.

In autumn, development stops and maturation starts, a process which comes to an end between November to March, the harvesting season in Spain. This is when the truffle starts to release its characteristic aroma to attract animals and the reproduction process starts all over again.

Buried Treasure

Black truffles have traditionally been found in wild areas. But, lately, wild truffles have become scarce, so trees previously mycorrhized with the truffle mycelium are now being planted. Such plantations have been set up in most of the historical truffle areas, specially in Soria (Castile-León) and Teruel (Aragón), in northeast Spain. The trees are carefully tended and pruned and, with time, begin to give the first fruits. The locals wait patiently with the typical calm demeanor that has characterized them generation after generation.

Looking into the eyes of one of these men, I get the impression he has been gazing for years over the jagged horizon of the valley, over the sharp silhouettes of the mountains. His name is Serafín Nieva. This is the Metauten valley, in the Navarre district of Urbasa Lóquiz Estella, opposite the town that gave it its name. He is the President of the Lóquiz Truffle Growers Association that operates in this area, close to the city of Pamplona. He scans the valley, with its five towns, its vineyards, its cereal fields and the herbs that grow freely all around. Behind us is the Truffle Interpretation Center in the town of Metauten.

Serafín is a lively conversationalist, but a touch of nostalgia creeps in at the end of every sentence. "A few years ago, all the land was cultivated. But there's not much soil and what remains is poor quality, so people have been leaving for the cities where they can make a lot more money. But for a while now it seems that the land is, in fact, good for truffles, at least good enough for some people to be able to stay. That's very important for us."

Turning his gaze from the quiet silhouette of Metauten, Serafín explains, "Truffle growing is a good option for the people in the valley. We are now producing truffles on more than 100 hectares / 247 acres of land, not counting the mountain, of course. I think this is the beginning of something that's going to grow in the future."

And So They Grow Trees

Another area where the truffle has helped the local economy is in the province of Soria (Castile-León). There are seven towns along the road between the city of Soria and Navaleno, and here things move at a different pace. The older inhabitants sit in front of the doors of their houses, slowly watching life -and the occasional vehicle- go by. Alone with their thoughts, they watch the mountains and the trees that have withstood many a cold winter. One of those mountains is home to the 600-hectare / 1,482 acres plantation of mycorrhized holm oaks that belong to the company Arotz.

I am greeted on the Arotz premises by José Ignacio Ruiz, who is responsible for the firm's exports. "These plantations have turned into one of the safest bets for this area. You can control the yield and guarantee annual production".

Arotz is one of Spain's most important truffle companies and a European standout in its sector. "Obviously," says José Ignacio Ruiz, "customers like to know their supplier can provide them with truffles every year, and we've been able to build up that confidence." But such certainty can only come with hard work in the field, with pruning, light plowing and especially irrigation in the summer.

Reaching New Heights

But even if the magic begins in the fields, giving under-populated and rural regions new sources of income that will preserve their lifestyle, it is in the kitchen where the final, majestic trick is produced. And indeed it does, for the imagination of a chef and a product as sublime as a truffle can truly create culinary masterpieces, full of subtleties and details.

As a sample, we asked a group of Spanish chefs what dishes they would make with black truffles. Santi Santamaría considers one of the best possible dishes to be truffle baked in clay, although he also mentions whole truffle in puff pastry or grated truffle in potato soup. Mario Sandoval, from his restaurant Coque in Humanes in Madrid, maintains that one of his favorites is fried free-range egg with truffle grated over the top.

Manuel de la Osa, from his Las Rejas restaurant in the town of Las Pedroñeras in Cuenca (Castile-León), prefers wild radish wafers filled with pieces of truffle in a green pineapple stock. And Paco Roncero, from La Terraza del Casino de Madrid, suggests cardoons with chestnuts and truffle. But both chefs and experts agree on the outstanding properties and versatility of the black truffle. As an ingredient in sauces and stews, it gives off its full aroma. But, according to Manuel de la Osa, they should not be cooked at a temperature greater than 70ºC / 158ºF, or the truffle's properties begin to lessen.

Another frequent way of using truffles is as the final garnish, grating it or placing thin slices on the top of the dish, preferably at the table. This way the temperature of the cooked dish brings out the truffle aroma, achieving an instant, almost magical result. Yet one of the most surprising comments, and a testament to the uniqueness and versatility of truffles, comes from Juan Pablo Felipe from El Chaflán restaurant in Madrid. He believes the black truffle can even be used to give different nuances to wine, and recommends placing a few pieces of Tuber melanosporum in wine glasses to offer new sensations, a new wine experience. "It's only an experiment really" says the chef, "but it's worth trying."