The fresh Cilantro leaves have a different taste from the seeds, most notably due to their citrus overtones. Some do not perceive the citrus flavor. In these cases, an unpleasant taste is experienced, which is frequently described as “soapy” or “metallic”. This may also be accompanied by a rank smell, causing avoidance of leaves. Belief that this is genetically determined may arise from the known genetic variation in taste perception of the synthetic chemical phenylthiocarbamide; however, no specific link has been established between coriander and a bitter taste perception gene.
The fresh leaves are an ingredient in many South Asian foods (particularly chutneys), in Chinese dishes and in Mexican dishes, particularly in salsa and guacamole and as a garnish. Chopped coriander leaves are a garnish on cooked dishes such as dal and curries. As heat diminishes their flavor quickly, coriander leaves are often used raw or added to the dish immediately before serving. In Indian and Central Asian recipes, coriander leaves are used in large amounts and cooked until the flavor diminishes. The leaves spoil quickly when removed from the plant, and lose their aroma when dried or frozen.
The dry fruits are known as coriander seeds or coriandi seeds. The word coriander in food preparation may refer solely to these seeds (as a spice), rather than to the plant itself. The seeds have a lemony citrus flavour when crushed, due to terpenes linalool and pinene. It is described as warm, nutty, spicy, and orange-flavored.
Coriander seed is a spice (Hindi namehania), in garam masala and Indian curries, which often employ the ground fruits in generous amounts together with cumin. It acts as a thickener. Roasted coriander seeds, called dhana dal, are eaten as a snack. It is the main ingredient of the two south Indian dishes: sambhar and rasam . Coriander seeds are boiled with water and drunk as indigenous medicine for colds.