The members of the botanical family known as Leguminosae were among the first cultivated plants in the Mediterranean. Legumes or beans (strictly, beans are a genus in the family Leguminosae) were also one of the first domesticated plants in the New World, appearing before 6000 B.C. Beans have among the highest protein content of all plant foods and are, for that reason, known as poor people’s food and are nutritionally important for people who cannot or choose not to eat meat. The amino acids found in beans are perfectly complemented by those in cereals, and these two foods are the first ones found preserved in archeological sites. When we see Mediterranean dishes with wheat and beans, or rice and lentils, or maize and peas, they are dishes that come very close to fulfilling our protein needs. But, in the words of the botanist Charles B. Heiser Jr., this was a “happy accident,” because primitive people knew nothing about amino acids or proteins.
(photo: Lentils, All-creatures.org)
Legume plants are also important for another reason. No other cultivated food plant has the ability that most legumes do of being able to obtain nitrogen from the atmosphere through the action of special bacteria that live in nodules on their roots. This nitrogen goes into the production of protein that makes itself available to humans when we eat the seeds. When the legume plant dies, the nitrogen is returned to the soil, helping other plants grow and building up soil fertility. Historically, this “green manuring” was important for the nutrient-poor Mediterranean soil. The Book of Daniel (1: 12) gives a sense of the importance of beans: “And let them give us pulse to eat, and water to drink.”
The Mediterranean legumes are of great variety, such as carob or St. John’s bread (Ceratonia siliqua). The pods of carobs, native to Syria, are eaten by some people in the Mediterranean because of their high sugar content, although they are used mostly for livestock feed. The grasspea or India pea (Lathyrus sativus) is a legume eaten in the Mediterranean as well as Asia, and when eaten in quantity without other foods can cause a disease known as lathyrism, which leads to a paralysis of the lower limbs that can be permanent. In the seventeenth-century Moroccan medical compendium, Tuhfat al-ahbāb, this legume is described as an aphrodisiac. The chickpea (Cicer arietinum) is native to the Near Eastern Mediterranean, as are lentils (Lens esculenta) and fava beans (Vicia faba), also known as the broad bean, Windsor bean, horse bean, Scotch bean, and English bean. A wild form of this plant is no longer known. The lupine bean (Lupinus albus) is native to the Near Eastern Mediterranean and so is bittervetch (Vicia ervilia) and the cultivated pea (Pisum sativum), of which there are of two kinds, the field pea, used mostly for dried peas and forage, and the garden pea with its high sugar content. Several Mediterranean legumes originated in Africa, such as the hyacinth bean (Lablab niger), native to the East African savanna and the cowpea (Vigna unguiculata), also known as the aspargus bean or yard-long bean, native to West Africa.
Today, the Mediterranean’s most famous beans, after the fava bean, lentil, and chickpea, are the New World beans. Phaseolus is the genus that has provided the most edible species of beans. This genus was unknown in the Mediterranean before the return of Columbus from his second voyage to the New World in 1493. Old World beans that were once classified as Phaseolus are now assigned to the genus Vigna. Four different species were domesticated in the Americas. Two of them, the scarlet runner bean (Phaseolus coccineus), originally from Mexico, and the tepary bean (Phaseolus acutifolius), are either grown for ornamental reasons or are now making a small comeback in some American culinary circles. Of the other two, the lima bean (Phaseolus lunatus, also called butter or sieva bean) is cultivated extensively and is originally from Peru. Lima beans’ distinctive taste comes from cyanogenetic glucoside, a cyanide-containing compound that appears in very small amounts in the beans grown in the United States.
(photo: flowering Lupinus albus, M. Hassler)
The common bean (Phaseolus vulgaris), also called the kidney bean, snap bean, French bean, haricot verts, flageolet, garden bean, filet bean, green bean, and string bean is the most widespread bean. The common green bean is a variety of this species whose pod is eaten at an immature stage. Horticultural or shell beans are P. vulgaris that have been picked when the pods have swelled but before the beans inside have dried. All the famous named beans you may have heard of--Kentucky Wonder, Blue Lake, cannellini, Jacob’s Cattle, and so on--are cultivars of P. vulgaris, of which there are now about 500 varieties.
Two other New World legumes have not made the jump to the Mediterranean kitchen: pacae beans (Inga feuillei), whose pods are nearly a yard long with seeds covered with a sweet white pulp that are sucked off; and jicama, a legume with an edible root.