Cardoons are used as a vegetarian source of enzymes for cheese production. In Portugal, traditional coagulation of the curd relies entirely on this vegetable rennet. This results in cheeses such as the Nisa (D.O.P.), with a peculiar earthy, herbaceous and a slightly citric flavour that bears affinity with full-bodied or fortified wines.
Cardoon has attracted recent attention as a possible source of biodiesel. The oil, extracted from the seeds of the cardoon, and called artichoke oil, is similar to safflower and sunflower oil in composition and use.
The cardoon (Cynara cardunculus), also called the artichoke thistle, cardone, cardoni, carduni or cardi, is a thistle-like plant which is member of the Aster family, Asteraceae; (or archaic: Daisy family, Compositae). It is a naturally occurring variant of the same species as the Globe artichoke, and has many cultivated varieties. It is native to the Mediterranean, where it was domesticated in ancient times.
The earliest description of the cardoon comes from the fourth century BC Greek writer Theophrastus. The cardoon was popular in Greek, Roman, and Persian cuisine. Cardoons remained popular in medieval and early modern Europe, and were common in the vegetable gardens of colonial America. They fell from fashion only in the late nineteenth century. In Europe, cardoon is still cultivated in France (Provence, Savoie, Lyonnais), Spain and Italy. In the Geneva region, where Huguenot refugees introduced it about 1685, the local variety cardy is considered a culinary specialty. "Before Cardoons are sent to table, the stalks or ribs are blanched by tying them together and wrapping them round with straw, which is also tied up with cord, and left so for about three weeks".
Cardoon stalks can be covered with small, nearly invisible spines that can cause substantial pain if they become lodged in the skin. Several spineless cultivars have been developed to overcome this, but care in handling is recommended for all types.
Cardoon requires a long, cool growing season (ca. 5 months), but it is frost-sensitive. It also typically requires substantial growing space per plant and hence is not much grown save where it is a regional favorite.
The cardoon is highly invasive and is able to adapt to dry climates. It has become a major weed in the pampas of Argentina and California; it is also considered a weed in Australia.
While the flower buds can be eaten much as the artichoke, more often the stems are eaten after being braised in cooking liquid. Battered and fried, the stems are also traditionally served at St. Joseph's altars in New Orleans.
The stalks, which look like large celery stalks, can be served steamed or braised. They have an artichoke-like flavor. Cardoons are available in the market only in the winter months. In the U.S.A., it is rarely found in stores, but available in farmers' markets, where it is available through May, June, and July. The main root can also be boiled and served cold. Acclaimed chef Mario Batali calls the cardoon one of his favorite vegetables and says they have a "very sexy flavor."
Cardoons are also an ingredient in one of the national dishes of Spain, the Cocido madrileño, a slow-cooking, one-pot, meat and vegetable dinner simmered in broth.
In the Abruzzi region of Italy, Christmas lunch is traditionally started with a soup of cardoons cooked in chicken broth with little meatballs (lamb or more rarely, beef), sometimes with the further addition of egg (which scrambles in the hot soup - called stracciatella) or fried chopped liver and heart.