Chicories and Endives: Bitterness Under Control

The original intense bitterness of lettuce, which came from a terpene compound called lactucin and its relatives, has been bred out of the cultivated forms. But a number of close lettuce relatives are cultivated and included in salads or cooked on their own especially to provide a civilized dose of bitterness. These are plants in the genus Cichorium, which include endive, escarole, chicory, and radicchio. Growers go to a lot of trouble to control their bitterness. Open rosettes of escaroles and endives are often tied into an artificial head to keep the inner leaves in the dark and relatively mild. And popular “Belgian endive,” also known as witloof (“white-head”), is a double-grown, slightly bitter version of an otherwise very bitter chicory. The plant is grown from seed in the spring, defoliated and dug up in the fall, and the taproot with its nutrient reserves kept in cold storage. The root is then either replanted indoors and kept covered with soil and sand as it leafs out, or else it’s grown hydroponically in the dark. The root takes about a month to develop a fist-sized head of white to pale green leaves, with a delicate flavor and crunchy yet tender texture. This delicacy is easily lost. Exposing the heads to light in the market will induce greening and bitterness in the outer leaves, and the flavor becomes harsh.