Truffles are precious underground mushrooms of the genus Tuber. They were listed for the first time as mushrooms in 1593 by Andrea Cesalpino – Italian botanist, anatomist, and doctor. A feature of truffles is that they grow near the roots of some certain species of trees with which they grow in symbiosis. They have a mutual benefit; a truffle extracts necessary sugars from the roots of the tree and in exchange, it supplies the tree with water, sodium, potassium and other useful mineral substances. Truffle grows from spores – very small seeds that have remained from a previous truffle growing in the same spot or were transferred by some animals that feed on truffles, e.g. snails. This is how the spores ‘embrace’ the roots of the tree and form mycorrhizae. During the process of mycorrhizae, a truffle exchanges minerals with tree roots, which leads to the development of hyphae (long, branched filaments) which begin to intertwine and eventually form a mycelium. In case of fertile soil and adequate moisture, the mycelium starts forming the sporocarp – an initial nucleus of the truffle.
The maturation lasts 5-8 weeks or even longer, depending on the truffle type, soil type, and climate. Truffles differ in shape, size, and flavor. A special feature of all truffles is their scent, which is much stronger than the scent of other mushrooms that grow on the surface. That is because the spores of the truffles spread below the ground, whereas the spores of other mushrooms spread above the ground. Once people searched for truffles with pigs, today we search for them with specially trained dogs. Dog training starts when dogs are puppies and it lasts for at least two years. A dog is able to smell a truffle once it releases the scent – when it matures. Fresh truffles have to be stored in a refrigerator and used in two-three weeks. Before use, they need to be cleaned under cold water with a brush, in order to remove soil from them.
Types of truffles in Slovenian Istria
In Slovenia, more specifically in Slovenian Istria, we can find truffles throughout the whole year. We are able to find black (Tuber Aestivum Vittadini, Tuber Uncinatum Vittadini, Tuber Brumale Vittadini, Tuber Brumale Moschatum de Ferry, Tuber Melanosporum Vittadini) as well as white truffles (Tuber Magnatum Pico, Tuber Borchii Vittadini/Tuber Albidum Pico).
Black Summer Truffle (Tuber Aestivum Vittadini)
Among all types of black truffles, the black summer truffle is the one we are able to find in biggest quantities. Its season is from April until October. Usually we find it just beneath the surface (approximately 2 cm), sometimes deeper. It grows in symbiosis with Turkey oak, downy oak common hazel, black and white hornbeam, English oak, oak, beech, black pine, poplar.
Black Autumn Truffle (Tuber Uncinatum Vittadini)
This type of truffle is known also as Burgundy truffle. Its appearance, smell and taste is very similar to the appearance, smell and taste of the black summer truffle. This type of truffle is also found just beneath the surface, its season is from September until December. Usually it grows in symbiosis with downy oak, Turkey oak, English oak, linden, poplar, willow, hornbeam, common hazel.
Black Winter Truffle (Tuber Brumale Vittadini)
We are able to find black winter truffle from December until March, just beneath the surface. Usually it grows in symbiosis with downy oak, holly oak, Turkey oak, black and white hornbeam, linden, common hazel, black pine and cedar.
Moscato Truffle (Tuber Brumale Moschatum de Ferry)
On the outside it is very similar to the black winter truffle. We are able to find it from December until March, just beneath the surface. It grows in symbiosis with the same trees as the black winter truffle: downy oak, holly oak, Turkey oak, linden, common hazel, black and white hornbeam, black pine and cedar.
Périgord Truffle (Tuber Melanosporum Vittadini)
Its name derives from Périgord – an ex province in southwest France, where it grows in big quantities. However, this truffle also grows in our beautiful Slovenian Istria, but in much smaller quantities. It grows 5-30 cm beneath the surface. It is the most valuable black truffle, known also as ‘the black diamond’. We are able to find this type of truffle from December until March. It grows in symbiosis with downy oak, holly oak, Turkey oak, linden, hazel, black hornbeam.
Prestigious White Truffle (Tuber Magnatum Pico)
Tuber Magnatum Pico is considered to be the king of all truffles, this is why we refer to it as ̒the white diamond̕. It is known also as the White Truffle of Alba, and this is why many people do not know that this type of truffle grows in Slovenian Istria as well. Its taste and smell are approximately ten times stronger than the taste and smell of black truffles, also its price is much higher. We are able to find it up to 40 cm below the surface, sometimes even deeper. It grows in symbiosis with white willow, white and black poplar, linden, black hornbeam, English oak, oak, downy oak.
Bianchetto White Truffle (Tuber Borchii Vittadini/Tuber Albidum Pico)
We search for this type of truffle from December until the end of March. They are small-sized, hence the name bianchetto (̒small white truffle̕ in Italian). It grows just beneath the surface, in symbiosis with black pine, stone pine, maritime pine, Aleppo pine, cedar, downy oak, Turkey oak, English oak, poplar, and willow.