There are hundreds of species of truffles that can be used, but the fruiting body of some (mostly in the genus "Tuber") are highly prized. The 18th-century French gastronome Brillat-Savarin called these truffles "the diamond of the kitchen". Edible truffles are are expensive because they are held in high esteem in "haute cuisine". They are used in the cuisine of many countries in Europe and worldwide. 