Coriander (Coriandrum sativum), also known as cilantro, Chinese parsley or dhania, is an annual herb in the family Apiaceae. Coriander is native to regions spanning from southern Europe and North Africa to southwestern Asia. It is a soft plant growing to 50 cm (20 in) tall. The leaves are variable in shape, broadly lobed at the base of the plant, and slender and feathery higher on the flowering stems. The flowers are borne in small umbels, white or very pale pink, asymmetrical, with the petals pointing away from the centre of the umbel longer (5–6 mm or 0.20–0.24 in) than those pointing toward it (only 1–3 mm or 0.039–0.118 in long). The fruit is a globular, dry schizocarp 3–5 mm (0.12–0.20 in) in diameter. Although sometimes eaten alone, the seeds are often used as a spice or an added ingredient in other foods.Coriander is popular as a scented stimulating substance and also an important culinary spice. It has been cultivated in different parts of the world for thousands of years now and is said to be one of the oldest known herbs, it can be traced as far back as 5,000 B.C. Coriander has been in wide use in the Middle East, Asia, and southern Europe, and also its origin can be traced back to ancient Egypt. The Romans took coriander with them to Britain. The British then introduced it to North America in 1670, where it took hold especially in Mexico and Latin America.The essential oil from this ancient herb has a place in aromatherapy. It helps to ease the mind and fight fatigue. It warms and calms the digestive system, relieves rheumatism and arthritic pain, muscular spasms and detoxifies the body. The essential oil is obtained from the seeds through steam distillation. It is also said to possess anti-inflammatory and anti-spasmodic properties, and hence, it is extensively used as effective massage oil to facilitate blood circulation as well as to relieve stiffness of the joints. Coriander is also used to flavour gin, vermouth, liqueurs and tobacco.
In perfumes, coriander is used to enrich the top and middle notes with its herbaceous, woody and spicy aura. Coriander oil combines nicely with bergamot, black pepper, cinnamon, clary sage, fennel, frankincense, ginger, grapefruit, juniper berry, lemon, neroli, nutmeg, orange, petitgrain, vetiver, and ylang-ylang.The fresh leaves are an ingredient in many Indian foods (such as chutneys and salads); in Chinese and Thai dishes; in Mexican cooking, particularly in salsa and guacamole and as a garnish; and in salads in Russia and other CIScountries. Chopped coriander leaves are a garnish on Indian dishes such as dal. As heat diminishes their flavour, 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 flavour diminishes.The leaves spoil quickly when removed from the plant, and lose their aroma when dried or frozen.
Different people may perceive the taste of coriander leaves differently. Those who like it say it has a refreshing, lemony or lime-like flavor, while those who dislike it have a strong aversion to its taste and smell, likening it to that of soap and bug.Twin studies have shown that 80% of identical twins shared the same preference for the herb, but fraternal twins agreed only about half the time, strongly suggesting a genetic component to the preference. In a genetic survey of nearly 30,000 people, two genetic variants linked to perception of coriander have been found, the most common of which is a gene involved in sensing smells.The gene, OR6A2, lies within a cluster of olfactory-receptor genes, and encodes a receptor that is highly sensitive to aldehyde chemicals.
Flavor chemists have found that the coriander aroma is created by a half-dozen or so substances, and most of these are aldehydes. Those who dislike the taste are sensitive to the offending unsaturated aldehydes, while simultaneously may also be unable to detect the aromatic chemicals that others find pleasant. Association between its taste and several other genes, including a bitter-taste receptor, have also been found.