MUSHROOMS - TRUFFLES 2013

MUSHROOMS
White Truffle
lat. Tuber magnatum Pico
Black Truffle
lat. Tuber melanosporum Vittadini

Thousands sorts of mushrooms live only in symbiosis with various other plants (the so called mycorrhiza, from the Greek mykes - mushroom and rhiza - root). Into that huge group of symbiotes fall also all kinds of truffles. This underground mushrooms form ectomycorrhiza with the plant’s root, they wind around primary roots of plants and create the mycoclena or the mantle. With this type of mycorrhiza mycelium enters intracellular spaces of plant’s roots and creates Hartig net which establishes a direct mutual connection with the plant.
White truffle grows in symbiosis with many sorts of plants: oak, lime-tree, poplar, willow and hazel, while black truffle lives in symbiosis with downy oak, European hop-hornbeam, hazel and various kinds of pine-trees. Apart from symbiosis, for successful growth of truffles very important is the quality of soil. As concerns soil acidity, white truffle and black truffle need alkaline soils (pH 7.5 - 8.4). The soil also must contain high quantity of calcium carbonate (CaCO₃), an adequate ratio of carbon and nitrogen (C/N) and low percentage of organic matter - which are all important factors for truffle growth.
In Croatia white truffle grows along all flows of rivers (Mirna, Raša, Pazinčica, Zrmanja, Cetina, Neretva, Sava, Una, Kupa, and Bosut). It also grows in Italy, Rumania, Bulgaria, Macedonia, Serbia and Albania. Black truffle needs for its growth sandy pebble soil and according to available data grows in Spain, France, Italy, Croatia, Serbia, Bulgaria, Macedonia, and Albania.
The white truffle’s fruiting body has pretty irregular shape and grows in average up to two to six centimetres wide, but can also be much bigger. At Gologorički Dol near Pićan in Istria en exemplar of white truffle was found weighting 1.31 kg and as such found also its place in the Guinness book of records. As with other species of mushrooms the mushroom pickers mistake the white truffle for whitish truffle (Tuber borchii), which grows from the end of September until the end of March in deciduous and evergreen forests and prefers south slopes and neutral soil. Black truffle can be mistaken for a variety of similar species of black truffles that grow at the same time and in the same habitat. First of all we mention the summer truffle (Tuber aestivum), which grows in summer, then the winter black truffle (Tuber brumale), that grows from the beginning of November until the end of March and is often confused with autumn black truffle (Tuber mesentericum), which grows in the same habitat as the black truffle). However, apart from superficiality, there is no danger since all mentioned black truffles are edible.
Black truffle has a more regular fruiting body than white truffle which can be roundish or bulbous in shape; the surface is blackish and roughly papillary. The spaces between the warts are on the basis and in younger plants explicitly brownish-red. On the cross section of the fruiting body a brownish-red gleba can be seen, interwoven with numerous sterile, white, branched small fibres. The smell of gleba is specific, sharp and very pleasant.
White truffle has a straw-whitish r or light ocher colour, sometimes also with the nuance of greenish. On the cross section of the fruiting body a compact gleba (mushroom body) can be seen, which is first white and after the ascospores get mature becomes light brownish to ocher brownish and is marmorised with numerous whitish sterile veins (small fibres). The smell of truffle is very characteristic and strong and reminds of the methane gas or fermented cheese smell.
Both truffles fall in the class of Ascomycetes because the spores they use for reproduction are produced in asci or in small basidia. White truffle has yellow-brown and wide elliptic spores with pointed ornament.
Both, white and black truffle are delicacies, with bigger exemplars of white truffle reaching on auctions extremely high prices, up to 245 000 EUR. Truffles are prepared in various ways but are best raw, because thus they keep their specific flavour in dishes, what makes them the most expensive mushrooms in the world.

Romano Božac, Ph.D.