Truffles are the fruit of an underground mushroom (hypogeous fungi).
This fruit, called "ascocarp", has a fleshy spore-bearing core (gleba) in a smooth or warty
casing (peridium). Truffles come from mycelium (the mushroom’s network of spindly
filaments), which thrives on the roots of oak or hazel trees. This association occurs
through mycorrhizae (a joint body resulting from the combination of a higher chlorophyll
plant and the mycelium of a fungus).

New filaments emerge from the mycorrhizae,
creating a new truffle that takes several
months to develop. When ripe, the truffle
releases spores that will germinate and then
produce the first filaments that will seep
into the rootlets of the tree.

The tree and the fungus enjoy a truly
symbiotic relationship. The tree benefits from
the mycorrhizae which help it grow by
producing various components such as sugar,
vitamins and hormones.

Their lifespan is between 200 and 290 days,
which allows about three months for
harvesting, from mid-December, for the first
spurt of Tuber melanosporum, to mid-March.
Tuber uncinatum, or Burgundy truffle,
is harvested usually between mid-September
and mid-January.

Initially white veined, it then darkens through melanization. Several weeks are needed
to develop its organoleptic qualities, its flavor, its texture, its appearance and its slightly
sulphurous scent, so unique from one truffle to another and from one species to another.

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