Ginger
Ginger  is the common name for the monocotyledonous perennial plant Zingiber officinale. The term is also used to describe the edible part of the plant which is commonly used as a spice in cooking throughout the world.  Often erroneously referred to as "ginger root", the edible section is actually the horizontal subterranean stem or rhizome of the plant.  The ginger plant has a long history of cultivation known to originate in China and then spread to India, Southeast Asia, West Africa, and the Caribbean.

# Chemistry
Ginger contains up to 3% of an essential oil that causes the fragrance of the spice. The main constituents are sesquiterpenoids with (-)-zingiberene as the main component. Lesser amounts of other sesquiterpenoids (-sesquiphellandrene, bisabolene and farnesene) and a small monoterpenoid fraction (-phelladrene, cineol, and citral) have also been identified.
The pungent taste of ginger is due to nonvolatile phenylpropanoid-derived compounds, particularly gingerols and shogaols. The latter are formed from the former when ginger is dried or cooked. Zingerone is also produced from gingerols during this process, and it is less pungent and has a spicy-sweet aroma.

# Culinary uses
Young ginger rhizomes are juicy and fleshy with a very mild taste.  They are often pickled in vinegar or sherry as a snack or just cooked as an ingredient in many dishes. They can also be stewed in boiling water to make ginger tea, to which honey is often added as a sweetener; sliced orange or lemon fruit may also be added. Mature ginger roots are fibrous and nearly dry.  The juice from old ginger roots is extremely potent and is often used as a spice in Chinese cuisine to flavor dishes such as seafood or mutton.
Ginger is also made into candy and used as a flavoring for cookies, crackers and cake, and is the main flavor in ginger ale-- a sweet, carbonated, non-alcoholic beverage, as well as the similar, but somewhat spicier beverage ginger beer. A ginger-flavored liqueur called Canton is produced in Jarnac, France. Green ginger wine is a ginger flavoured wine produced in the United Kingdom by Crabbie's and Stone's and traditionally sold in a green glass bottle. Ginger is also used as a spice added to hot coffee and tea.
In Arabic, ginger is called Zanjabil and in some parts of the Middle East ginger powder is used as a spice for coffee.
In India, ginger is called "Shoonti" in Kannada language, Allam  in Telugu, Inji in Tamil and Malayalam, Alay in Marathi and Adrak in Hindi and Urdu. Fresh ginger is one of the main spices used for making pulse and lentil curries and other vegetable preparations. It is used fresh to spice tea especially in winter. Also, ginger powder is used in certain food preparations that are made particularly for expecting women and feeding mothers, the most popular one being Katlu which is a mixture of gum resin, ghee, nuts and sugar.
In south India, ginger is used in the production of a candy called Inji-murappa ("ginger candy" from Tamil). This candy is mostly sold by vendors to bus passengers in bus stops and in small tea shops as a locally produced item. Candied ginger is also very famous around these parts. Additionally, in Tamil Nadu, especially in the Tanjore belt, a variety of ginger which is less spicy is used when tender to make fresh pickle with the combination of lemon juice or vinegar, salt and tender green chillies. This kind of pickle was generally made before the invention of refrigeration and stored for a maximum of 4-5 days. The pickle gains a mature flavor when the juices cook the ginger over the first 24 hours.  Ginger is also added as a flavouring in tea.
In Japan, ginger is pickled to make beni shoga and gari or grated and used raw on tofu or noodles.
In Western cuisine, ginger is traditionally restricted to sweet foods, such as ginger ale, gingerbread, ginger snaps, ginger cake and ginger biscuits.
Powdered dry ginger root (ginger powder) is typically used to add spiciness to gingerbread and other recipes. Ground and fresh ginger taste quite different and ground ginger is a particularly poor substitute for fresh ginger. Fresh ginger can be successfully substituted for ground ginger and should be done at a ratio of 6 parts fresh for 1 part ground. You generally achieve better results by substituting only half the ground ginger for fresh ginger.
In Myanmar, ginger is used in a salad dish called gyin-tho, which consists of shredded ginger preserved in oil, and a variety of nuts and seeds.
Indonesia has a famous beverage that called Wedang Jahe, which is made from ginger and palm sugar.
In traditional Korean Kimchi, ginger is finely minced and added to the ingredients of the spicy paste just before the fermenting process.
In South East Asia, the flower of a type of ginger is used in cooking. This unopened flower is known in the Malay language as Bunga Kantan, and is used in salads and also as garnish for sour-savoury soups, like Assam Laksa.
Ginger has a sialagogue action, stimulating the production of saliva.

# Medical uses
The medical form of ginger historically was called "Jamaica ginger"; it was classified as a stimulant and carminative, and used frequently for dyspepsia and colic. It was also frequently employed to disguise the taste of medicines.  Ginger is on the FDA's 'generally recognized as safe' list, though it does interact with some medications, including warfarin.  Ginger is contraindicated in people suffering from gallstones as the herb promotes the release of bile from the gallbladder.  Ginger may also decrease joint pain from arthritis, though studies on this have been inconsistent, and may have blood thinning and cholesterol lowering properties that may make it useful for treating heart disease. 
The characteristic odor and flavor of ginger root is caused by a mixture of zingerone, shoagoles and gingerols, volatile oils that compose about one to three percent of the  weight of fresh ginger.  In laboratory animals, the gingerols increase the motility of the gastrointestinal tract and have analgesic, sedative, antipyretic and antibacterial properties 

## Nausea
Ginger has been found effective by multiple studies for treating nausea caused by seasickness, morning sickness and chemotherapy, though ginger was not found superior over a placebo for post-operative nausea.
Modern research on nausea and motion sickness used approximately 1 gram of ginger powder daily.  Though there are claims for efficacy in all causes of nausea, the Physicians Desk Reference recommends against taking ginger rhizomes for morning sickness commonly associated with pregnancy due to possible mutagenic effects, though  Chinese women have traditionally used ginger rhizomes during pregnancy to combat morning sickness and the Natural Medicines Comprehensive Database states that it is likely safe for use in pregnancy when consumed in food-amounts.

# Folk medicinal uses
Tea brewed from this root is a folk remedy for colds.  Ginger ale and ginger beer have been recommended as "stomach settlers" for generations in countries where the beverages are made and ginger water was commonly used to avoid heat cramps in the US.  Ginger has also been historically used to treat inflammation, which some scientific studies support while others show ginger to be no better than a placebo or ibuprofen.

## Local uses
In the West, powdered dried ginger root is made into capsules and sold in pharmacies for medicinal use.
- In the United States, ginger is generally recognized as safe by the Food and Drug Administration, though it is not approved for the treatment or cure of any disease and is sold as an unregulated dietary supplement
- In India, ginger is applied as a paste to the temples to relieve headache and consumed when suffering from a cold
- In Myanmar, ginger and local sweet (Htan nyat) which is made from palm tree juice are boiled together and taken to prevent the flu
- In China, a drink made with sliced ginger cooked in sweetened water or a cola is used as a folk medicine for common cold
- In Indonesia, a type of ginger known as Jahe is used as a herbal preparation to reduce fatigue, reducing "winds" in blood streams, prevent and cure rheumatism and controlling poor dietary habits
- In Democratic Republic of the Congo, ginger is crushed  and mixed with mango-tree sap to make Tangawisi juice, which is considered as "universal" panacea.
- In Ivory Coast, ginger is ground and mixed with orange, pineapple and lemon to produce a very refreshing juice called Nyamanku.

# Reactions
Allergic reactions to ginger generally result in a rash and though generally recognized as safe, ginger can cause heartburn, bloating, gas, belching and nausea, particularly if taken in powdered form.  Unchewed fresh ginger may result in intestinal blockage, and individuals who have had ulcers, inflammatory bowel disease or blocked intestines may react badly to large quantities of fresh ginger.  Ginger can also adversely affect individuals with gallstones.  There are also suggestions that ginger may affect blood pressure, clotting, and heart rhythms.

# Horticulture
Ginger produces clusters of white and pink flower buds that bloom into yellow flowers.  Because of the aesthetic appeal and the adaptivity of the plant to warm climates, ginger is often used as landscaping around subtropical homes. It is a perennial reed-like plant with annual leafy stems, three to four feet high.
Historical methods of gathering the root describes, when the stalk withers, it is immediately scalded, or washed and scraped, in order to kill it and prevent sprouting. The former method, applied generally to the older and poorer roots, produces Black Ginger; the latter, gives White Ginger. The natural color of the "white" scraped ginger is a pale buff--it is often whitened by bleaching or liming, but generally at the expense of some of its real value.

# References in popular culture
- To members of the Race, an alien species in Harry Turtledove's best-selling novel series Worldwar, ginger is a highly addictive, psychoactive drug, with an effect similar to that of cocaine or PCP in humans.
- In Cockney rhyming slang, ginger is a derogatory euphemism for homosexual.  The original slang rhymed queer with ginger beer.
- In the west of Scotland (particularly Glasgow), ginger is a term for any carbonated soft drink.
- Before the First World War, it was common for mounted regiments to receive large vats of root ginger before public ceremonies, which were peeled and cut into suppositories for the horses. The burning sensation made the horses hold their tails up; this practice is called Figging or feaguing.
- Ginger is also a common slang term in Great Britain for red-haired individuals. This term is also used in the South Park in episode Ginger Kids. In Harry Potter and the Deathly  Hallows, the drunk men yelling at Hermione used the term "Ginger" to describe Ron's red hair.

# Production trends
In 2005, China continued to lead the world in ginger production with a global share of almost 25% followed by India, Nepal and Indonesia.

# Similar species
Myoga (Zingiber mioga Roscoe) appears in Japanese cuisine; the flower buds are the part eaten.
Another plant in the Zingiberaceae family, galangal, is used for similar purposes as ginger in Thai cuisine. Galangal is also called Thai ginger.  Also referred to as galangal, fingerroot (Boesenbergia rotunda), or Chinese ginger or the Thai krachai, is used in cooking and medicine.
A dicotyledonous native species of eastern
North America, Asarum canadense, is also known as "wild ginger", and its root has similar aromatic properties, but it is not related to true ginger and should not be used as a substitute because it contains the carcinogen aristolochic acid.  This plant is also a powerful diuretic, or urinary stimulator.  It is part of the Aristolochiaceae family.