Amorphophallus konjac –also known as konnyaku, [2][a] and konjac[b]– is a plant species native to Yunnan in southwestern China, which has an edible corm. It is also known as devil's tongue, [2] voodoo lily, snake palm, or elephant yam.[c] It is a relative of the titan arum (A. titanum), one of the largest flowering plants in the world and a congener of konjac.[3] Konjac is cultivated in warm subtropical to tropical areas of East and Southeast Asia, from China and Japan south to Indonesia and Vietnam (USDA hardiness zone 6–11). It is a perennial plant, growing from a large corm up to 25 cm (10 in) in diameter. The single leaf is up to 1.3 m (4 ft) across, bipinnate, and divided into numerous leaflets.[4] The flowers are produced on a spathe enclosed by a dark purple spadix up to 55 cm (22 in) long. The food made from the corm is known in English by its Japanese name, konnyaku.[5]: 595 [2] Two basic types of cake are made from konjac, white and black, as well as noodles, called shirataki. The corm of the konjac is often colloquially referred to as a yam, though it is not related to tubers of the family Dioscoreaceae. History Wild forms grow naturally in China and Southeast Asia.[6] Konjac has been used in Japan since the 6th century, as a supposed medicinal food.[7] Japanese documents from around the 18th century mentions its intestinal cleansing property.[8]: 00:09:44  Nakajima Toemon developed a method to produce konjac flour in 1776, which are more durable for transportation and storage, contributing to their wider consumption.[8]: 00:10:44  Cultivation and use Amorphophallus konjac in bloom Amorphophallus konjac male (top) and female (bottom) flowers Japanese konjac gel, with hijiki seaweed mixed in Konjac corm used for preparing food Sashimi konnyaku, usually served with a miso-based dipping sauce rather than soy sauce Konjac is grown in East and Southeast Asia and it is prized for its large starchy corms, used to create a flour and jelly of the same name. It is also used as a vegan substitute for gelatin. In Japan, over 90% of all domestically produced konjac is made in Gunma Prefecture.[9] East Asia In Japanese cuisine, konjac (konnyaku) appears in dishes such as oden. It is typically mottled grey and firmer in consistency than most gelatins. It has very little flavor; the common variety tastes vaguely like salt, usually with a slightly oceanic taste and smell (from the seaweed powder added to it, though some forms omit the seaweed). In Japan, it is valued more for its texture than flavor. Ito konnyaku (糸蒟蒻) is a Japanese food consisting of konjac cut into noodle-like strips. It is usually sold in plastic bags with accompanying water, which is drained before cooking. The name literally means 'thread-konjac'. Japanese konnyaku is made by mixing konjac flour with water and limewater.[10] Konjac cannot be eaten raw because it contains oxalic acid.[8]: 00:05:07  The product come in various shades of gray; konnyaku made from corm are naturally dark, while those made from konjac flour are white.[8]: 00:05:42  Hijiki is often added for the characteristic dark color and flavor. It is then boiled and cooled to solidify. Konjac made in noodle form is called shirataki and used in foods such as sukiyaki and gyūdon.[5]: 595  Konjac is consumed in parts of China's Sichuan province; the corm is called moyu (Chinese: 魔芋; lit. 'demonic taro'), and the jelly is called "konjac tofu" (魔芋豆腐 móyù dòufu) or "snow konjac" (雪魔芋 xuě móyù). In Vietnam, konjac is mainly grown in An Giang province. The corms are collected and processed into flour. The flour is used to make drinks, cakes, and noodles.[11] Traditional medicine The dried corm of the konjac plant contains around 40% glucomannan gum. This polysaccharide makes konjac jelly a viscous substance that may be used in traditional Chinese medicine.[12] Fruit jelly Konjac can also be made into a popular East Asian fruit jelly snack, known variously in the US as lychee cups (after a typical flavor) or konjac candy, usually served in bite-sized plastic cups.