The Loire Valley and Black Truffles
Although now known for its outstanding natural beauty, magnificent châteaux and stylish wine, in the mid-1800s the Loire Valley produced the most Black Winter Truffles in the world – in excess of 1,000 tons. This was due to the combination of ideal soil conditions and climate. As a result of the decimation caused by the First World War, the production of Black Winter Truffles in France diminished dramatically – France now produces around just 60 tons annually, making them a prized rarity.
French Black Winter Truffles
Also known as the ‘Black Diamond’, this is the most prized and valuable French truffle, which develops on the roots of slow-growing trees, such as oak or hazel. Its botanical name is Tuber melanosporum, but they are also referred to as Perigord Black Truffles, after the region in France where they grow in the wild. Known for their nutty, delicate yet intricate flavour, French truffles are only available in the European winter time (December to January).
The white Italian Alba or Piedmont Truffle, technically referred to as Tuber magnatum, is also harvested during the winter and can never be cultivated. Be aware of the ‘whiteish truffle’ (Tuber borchii) which is a similar species, although smaller and less aromatic.
These grow during the European summer time (not to be confused with summer truffles, see below) which is winter in Australia. This ‘New World truffle’ with its inverse harvest time has helped unlock truffles’ inaccessibility, beyond the usual seasonality that has helped shape their rarity. The Australian truffles are also Tuber melanosporum.
These are used as a substitute for the Black Winter Truffle and as the name suggests, they are grown in (European) summer time. Tuber aestivum are paler in colour than the Black Winter Truffle - see picture - and have a less intense aroma. They are harvested May to August. A large part of their market is now shared with the Australian Truffle.
One of the main issues the booming truffle business in China faces, according to various sources, is getting their particular variety of truffles (Tuber himalayensis) out of the country before they expire. They are known to be of powdery, poor quality, partly due to the export issues and also partly due to the soil quality and the unknown provenance.