Licorice — Liquorice or licorice is the root of Glycyrrhiza glabra, from which a sweet flavour can be extracted. The liquorice plant is a legume (related to beans and peas) and native to southern Europe and parts of Asia. It is a herbaceous perennial, growing to 1 m in height, with pinnate leaves about 7–15 centimetres (3–6 inches) long, with 9–17 leaflets. The flowers are 0.8–1.2 cm (1/3 to 1/2 inch) long, purple to pale whitish blue, produced in a loose inflorescence. The fruit is an oblong pod, 2–3 centimetres (about 1 inch) long, containing several seeds.
Liquorice is grown as a root crop mainly in southern Europe. Historically, it is also linked with Pontefract in Yorkshire, England, which has an annual liquorice festival. Very little commercial liquorice is grown in North America, where it is replaced by a related native species, American Licorice (G. lepidota), which has similar uses. In northern China, the related Chinese Liquorice (G. uralensis) is cultivated for use in traditional Chinese medicine.
Liquorice grows best in deep, fertile, well-drained soils, with full sun, and is harvested in the autumn two to three years after planting.
Liquorice extract is produced by boiling liquorice root and subsequently evaporating most of the water (in fact, the word ‘liquorice’ is derived from the Ancient Greek words for ‘sweet root’). Liquorice extract is traded both in solid and syrup form. Its active principle is glycyrrhizin, a sweetener more than 50 times as sweet as sucrose which also has pharmaceutical effects. G. uralensis contains this chemical in much greater concentration.
Powdered liquorice root (licorice root) is an effective expectorant, and has been used for this purpose since ancient times, especially in Ayurvedic medicine where it is also used in tooth powders. Modern cough syrups often include liquorice extract as an ingredient. Additionally, liquorice may be useful in conventional and naturopathic medicine for both mouth ulcers and peptic ulcers. Non-prescription aphthous ulcer treatment CankerMelts incorporates glycyrrhiza in a dissolving adherent troche. Liquorice is also a mild laxative and may be used as a topical antiviral agent for shingles, ophthalmic, oral or genital herpes.