What are the methods for identifying the macroscopic characteristics of Gastrodia elata and fake Gastrodia elata?
In recent years, similar plant tubers have often appeared on the market, passing off fake products as genuine and passing off fake products as genuine Gastrodia elata. In order to reduce mistakes and clean up the market, the macroscopic characteristics of several easily confused fake Gastrodia elata are introduced here:
Gastrodia elata: "Parrot beak, concave navel, outside has ring spots and dried ginger skin, rosin-like cross-section must be remembered." This is the mnemonic for identifying true and false Gastrodia elata. In this mnemonic, the rosin-like cross-section is an important basis for judging the authenticity of Gastrodia elata. The dried tuber of authentic Gastrodia elata is long elliptical, often flattened, shrunken and curved, 6-13 cm long, 2-6 cm in diameter. One end has a residual stem base or a red-brown withered bud (commonly called parrot beak), and the other end has a round navel-shaped scar (commonly called concave navel); the epidermis is pale yellow or earthy yellow, slightly transparent or opaque, with transverse ring lines formed by dot-like protrusions; the texture is hard, not easy to break, the cross-section is slightly flat, horny; the taste is slightly pungent and sweet, and when chewed it is crisp and somewhat sticky. Those with a hard and heavy texture, a parrot beak, and a bright cross-section without a hollow center are winter Gastrodia elata and are of better quality; those with a light and spongy texture, a residual stem base, a dull cross-section, and a hollow center are spring Gastrodia elata and are somewhat inferior to winter Gastrodia elata.
Tubers passed off as Gastrodia elata include Mirabilis jalapa, Dahlia pinnata, potato, and other processed products.
Mirabilis jalapa is the root of the plant Mirabilis jalapa in the family Nyctaginaceae. This product is long conical, sometimes branched, mostly already flattened, 6-12 cm long, 1.5-4 cm in diameter, the surface pale yellow-white, grayish yellow-white or grayish brown-yellow, semi-transparent, with longitudinal groove lines and fibrous root scars, sometimes twisted, the apex has stem scars of varying lengths, hard in texture, not easy to break, the cross-section uneven, yellow-white or pale yellow-brown, horny, sometimes concentric ring lines are visible.
Dahlia pinnata is the tuberous root of the plant Dahlia pinnata in the family Asteraceae. This product is long spindle-shaped, slightly curved, the surface gray-white or nearly white, with obvious irregular longitudinal lines, the apex has a stem base scar, the apex and the end are fibrous, hard in texture and not easy to break, the cross-section nearly white, horny. Potato is the tuber of the plant potato in the family Solanaceae, formed by flattening; the imitation product is flattened oval, the surface has irregular longitudinal grooves and shallow grooves, no dot-like ring lines, or has imitation patterns, sweet in taste, and tastes of potato when chewed.
Other fake products mostly have small pieces of Gastrodia elata or foreign matter added into the cracks of Gastrodia elata. After such fake products are cut open, adulterants such as iron nails and tin particles can often be seen in the cross-section.