Truffle is the common noun designating the fruiting bodies (sporocarps) of fungi, in the genus Tuber, whose entire life cycle takes place in the earth (subterranean). Truffles must live in symbiotic relationships with certain trees in order to produce the precious sporocarps. They present an external skin called peridium, which can be smooth or bumpy and of varying colours.

The inner portion (the flesh or gleba) can vary in colour, from white to black and from pink to brown, and presents veins, varying in size and branching, which define cavities containing large cells (spore sacs or ascus), which in turn bear the spores. The morphological characteristics of the peridium, gleba, ascus and spores, together with the size and the sensory characteristics, will determine the different species of truffle.

Composition

Extremely highly-priced truffles are in fact composed, for over 80%, of nothing but water. The following table shows the composition in the percentage of a Tuber melanosporum (black truffle) and a Tuber magnatum (white truffle) (by Coli R., Maurizi Coli A., Granetti B., Damiani P.).

In both truffles, the prevalent minerals are potassium, calcium, sodium, magnesium, iron, zinc and copper. The value of truffle lies therefore not in its nutritional value but in its ability to provide pleasure to the consumers. It is for the same reason that market prices vary greatly from one species to the other, although the chemical composition is very similar.

 

T. Magnatum Pico – T. Melanosportum Vitt.

Water
82,58 – 82,80
Non-protein nitrogen
0,23 – 0,14
Soluble Carbohydrates
0,36 – 0,17
Ash
1,97 – 1,70
Proteins
4,13 – 4,50
Dietary fibre
8,43 – 8,13
Total nitrogen
0,88 – 0,87
Fats
2,08 – 1,90