Clove

This article is about the spice. For other uses, see Clove (disambiguation).

Clove
File:Syzygium aromaticum - Köhler–s Medizinal-Pflanzen-030.jpg
Scientific classification
Kingdom:	Plantae
Phylum:	Angiosperms
(unranked):	Eudicots
(unranked):	Rosids
Order:	Myrtales
Family:	Myrtaceae
Genus:	Syzygium
Species:	S. aromaticum
Binomial name
Syzygium aromaticum (L.) Merrill & Perry
Synonyms
Caryophyllus aromaticus L. Eugenia aromatica (L.) Baill. Eugenia caryophyllata Thunb. Eugenia caryophyllus (Spreng.) Bullock & S. G. Harrison

Cloves are the aromatic flower buds of a tree in the family Myrtaceae, Syzygium aromaticum, native to the Maluku Islands in Indonesia, commonly used as spice. Cloves are harvested primarily in Indonesia, India, Madagascar, Zanzibar, Pakistan, Sri Lanka, and the largest producer, Pemba Island, just off the coast of Tanzania.

The clove tree is an evergreen growing to 8–12 m tall, having large leaves and sanguine flowers grouped in terminal clusters. The flower buds begin as a pale hue before gradually becomimg green, then transitioning to a bright red and are ready for collection. Cloves are harvested at 1.5–2.0 cm long, and consist of a long calyx, terminating in four spreading sepals, and four unopened petals forming a small central ball.

Uses

File:ClovesDried.jpg

Dried cloves

File:COLLECTIE TROPENMUSEUM Kruidnagelmodel van een prauw TMnr A-4405a.jpg

Clove model of a proa

File:2005clove.PNG

Clove output in 2005

Cloves are used in the cuisine of Asian, African, and the Near and Middle East, lending flavour to meats, curries, and marinades, as well as complement to fruit such as apples, pears, or rhubarb.

In Mexican cuisine, cloves are best known as clavos de olor, and often accompany cumin and cinnamon.

About 85% of cloves' powerful taste is imparted by the chemical eugenol, and the quantity of the spice required is typically relatively small. It pairs well with cinnamon, allspice, vanilla, red wine, and basil, as well as onion, citrus peel, star anise, or peppercorns.

Nonculinary uses

The spice is used in a type of cigarette called kretek in Indonesia. They have been smoked throughout Europe, Asia, and the United States. In 2009, clove cigarettes (as well as fruit- and candy-flavored cigarettes) were outlawed in the US. Cigarettes containing clove are now classified as cigars when sold in the US.

Clove may be used as an ant repellant.

They can be used as to make a fragrant pomander when combined with an orange.

Traditional medicinal uses

Cloves are used in Indian Ayurvedic medicine, Chinese medicine, and western herbalism and dentistry where the essential oil is used as an anodyne (painkiller) for dental emergencies. Cloves are used as a carminative, to increase hydrochloric acid in the stomach and to improve peristalsis. Cloves are also said to be a natural anthelmintic. The essential oil is used in aromatherapy when stimulation and warming are needed, especially for digestive problems. Topical application over the stomach or abdomen are said to warm the digestive tract. Applied to a cavity in a decayed tooth, it also relieves toothache.

In Chinese medicine, cloves or ding xiang are considered acrid, warm, and aromatic, entering the kidney, spleen and stomach meridians, and are notable in their ability to warm the middle, direct stomach qi downward, to treat hiccough and to fortify the kidney yang. Because the herb is so warming, it is contraindicated in any persons with fire symptoms and according to classical sources should not be used for anything except cold from yang deficiency. As such, it is used in formulas for impotence or clear vaginal discharge from yang deficiency, for morning sickness together with ginseng and patchouli, or for vomiting and diarrhea due to spleen and stomach coldness.

Cloves may be used internally as a tea and topically as an oil for hypotonic muscles, including for multiple sclerosis. This is also found in Tibetan medicine. Some recommend avoiding more than occasional use of cloves internally in the presence of pitta inflammation such as is found in acute flares of autoimmune diseases.

Modern medicinal uses and pharmaceutical preparations

Template:Medref While it has been used historically in the West for dental pain, the U.S. Food and Drug Administration (FDA) has reclassified eugenol (one of the chemicals contained in clove oil), downgrading its effectiveness rating. The FDA now believes not enough evidence indicates eugenol to be effective for toothache pain. Clove oil seems to be safe when applied to the skin; however, frequent and repeated application of clove oil in the mouth on the gums can sometimes cause damage to the gums, tooth pulp, mucous membranes, and skin.

Studies to determine its effectiveness for fever reduction, as a mosquito repellent, and to prevent premature ejaculation have been inconclusive. Clove may reduce blood sugar levels.

Tellimagrandin II is an ellagitannin found in S. aromaticum with antiherpesvirus properties.

The buds have antioxidant properties.

Clove oil can be used to anesthetize fish, and prolonged exposure to higher doses (the recommended dose is 400 mg/l) is considered a humane means of euthanasia.

In addition, clove oil is used in preparation of some toothpastes, laxative pills, and Clovacaine solution which is a local anesthetic used in oral ulceration and inflammation. Eugenol (or clove oil generally) is mixed with zinc oxide to be a temporary filling.

Adulteration

Clove stalks are slender stems of the inflorescence axis which show opposite decussate branching. Externally, they are brownish, rough, and irregularly wrinkled longitudinally with short fracture and dry, woody texture.

Mother cloves (anthophylli) are the ripe fruits of cloves which are ovoid, brown berries, unilocular and one-seeded. This can be detected by the presence of much starch in the seeds.

Brown cloves are expanded flowers from which both corollae and stamens have been detached.

Exhausted cloves have almost or all of the oil removed by distillation. They yield no oil and are darker in color.

History

Until modern times, cloves grew only on a few islands in the Maluku Islands (historically called the Spice Islands), including Bacan, Makian, Moti, Ternate, and Tidore. In fact, the clove tree believed to be the oldest in the world, named "Afo", is found on Ternate—the tree being between 350 and 400 years old. Seedlings from this tree were stolen by a Frenchman named Poivre in 1770, transferred to France, and then later to Zanzibar, which is today the world's largest producer of cloves.

Until cloves were grown outside of the Maluku Islands, they were traded like oil, with a forced limit on exportation. As the Dutch East India Company consolidated its control of the spice trade in the 17th century, they sought to gain a monopoly in cloves as they had in nutmeg. However, "unlike nutmeg and mace, which were limited to the minute Bandas, clove trees grew all over the Moluccas, and the trade in cloves was way beyond the limited policing powers of the corporation."

In the third century BC, a Chinese leader in the Han Dynasty required those who addressed him to chew cloves so as to freshen their breath. Cloves were traded by Muslim sailors and merchants during the Middle Ages in the profitable Indian Ocean trade, the clove trade is also mentioned by Ibn Battuta and even famous One Thousand and One Nights characters such Sinbad the Sailor are known to have bought and sold cloves. Archeologists have also found cloves within a ceramic vessel in Syria along with evidence dating the find to within a few years of 1721 BC.

Active compounds

File:Eugenol acsv.svg

The compound eugenol is responsible for most of the characteristic aroma of cloves.

Eugenol comprises 72-90% of the essential oil extracted from cloves, and is the compound most responsible for the cloves' aroma. Other important essential oil constituents of clove oil include acetyl eugenol, beta-caryophyllene and vanillin, crategolic acid, tannins such as bicornin, gallotannic acid, methyl salicylate (painkiller), the flavonoids eugenin, kaempferol, rhamnetin, and eugenitin, triterpenoids such as oleanolic acid, stigmasterol, and campesterol, and several sesquiterpenes.

Eugenol can be toxic in relatively small quantities—as low as 5 ml.

See also

• Cinnamomum aromaticum
• Gallic acid
• Insect repellent