Black truffle. Tuber melanosporum, called the black truffle, P矇rigord truffle or French black truffle is a species of truffle native to Southern Europe. It is one of the most expensive edible mushrooms in the world. In cooking, black truffles are used to refine the taste of meat, fish, soups and risotto. Unlike white truffles, the aroma of black truffles does not diminish when they are heated, but becomes more intense. A fungus is any member of a large group of eukaryotic organisms that includes microorganisms such as yeast and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, Fungi, which is separate from plants, animals, protists, and bacteria. They have long been used as a source of food, as a leavening agent for bread, and in fermentation of various food products, such as wine, beer, and soy sauce. Since the 1940s, fungi have been used for the production of antibiotics, and, more recently, various enzymes produced by fungi are used industrially and in detergents. The fruiting structures of a few species contain psychotropic compounds and are consumed recreationally or in traditional spiritual ceremonies. Little is known of the true biodiversity of Kingdom Fungi, which has been estimated at 1.5 million to 5 million species, with about 5% of these having been formally classified. Undated, no illustrator credited.