Tuber borchii


Tuber borchii, known as the whitish truffle or bianchetto truffle, is a small, common species of edible truffle excellent for use in cuisine.

Taxonomy

It was given its name by Carlo Vittadini from Latin borchii.

Description

It is from in size and rounded, with a tuber-like appearance, often bony or irregular. The exterior is slightly velvety and white at first, and when mature it has a smooth, reddish ochre surface with brown markings. It has a compact consistency and, when sectioned, the interior is whitish when young, light ochre or pinkish brown with age. A series of white, twisted and branched veins run through the interior. Young specimens give off a pleasant smell, but when mature they give off an unpleasant smell reminiscent of kitchen gas. The flavor is described by some as garlicky, by others as similar to hazelnuts.
Seen through a microscope, the spores have an ellipsoidal to rounded shape, measuring 35–55 × 25–40 microns, and are brown in colour. The ascii are rather rounded and contain 1 to 4 spores.
There are many similar species: Tuber asa, Tuber oligospermum and Tuber puberulum.

Habitat and distribution

Whitish truffles often grow in oak groves, and less frequently under conifers. Like most truffles, it bears fruit underground, although not very deep. It bears fruit from winter to early summer, in coastal or low-lying areas. It is highly adaptable to different environments: although it prefers calcareous sandy soils it also bears fruit in T. melanosporum habitat at higher altitudes. It grows well in soils with a pH of 7–8, as well as in subalkalines with a pH of 6–7, although occasionally it also grows in soils with a pH as low as 5.2.
It is found throughout Europe: from Finland to Italy and the Iberian Peninsula, and from Ireland and Great Britain to Hungary and Poland, very common in France, including Corsica.

Cultivation

It is harvested from winter to spring, unlike Tuber magnatum, which is collected in autumn and early winter. It sells for some 300–400 €/kg. Although it is not as sought after as T. magnatum or T. melanosporum, there are several reasons for its cultivation: it fruits early in new plantations, is adaptable to different ecological niches, is not extremely specific to host plants, and lastly, it is very competitive with other ectomycorrhizal fungi.
Mycorrhiza Biotech of Gibsonville, North Carolina, has been developing methods for commercial production of bianchetto truffles in North Carolina, reportedly producing as much as an estimated in a single yield.