|Syzygium aromaticum |
(L.) Merrill & Perry syn. (Eugenia caryophyllata)
The clove tree is an evergreen that grows to a height ranging from 8–12 m, having large square leaves and sanguine flowers in numerous groups of terminal clusters. The flower buds are at first of a pale color and gradually become green, after which they develop into a bright red, when they are ready for collecting. Cloves are harvested when 1.5–2 cm long, and consist of a long calyx, terminating in four spreading sepals, and four unopened petals which form a small ball in the center.
Nomenclature and taxonomy
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Cloves have historically been used in Indian cuisine (both North Indian and South Indian). In North Indian cuisine, it is used in almost all rich or spicy dishes as an ingredient of a mix named garam masala, along with other spices, although it is not an everyday ingredient for home cuisine, nor is it used in summer very often. In the Maharashtra region of India it is used sparingly for sweet or spicy dishes, but rarely in everyday cuisine. In Ayurvedic medicine it is considered to have the effect of increasing heat in system, hence the difference of usage by region and season. In south Indian cuisine, it is used extensively in biryani along with "cloves dish" (similar to pilaf, but with the addition of other spices), and it is normally added whole to enhance the presentation and flavor of the rice.
Dried cloves are also a key ingredient in Indian masala chai, spiced tea, a special variation of tea popular in some regions, notably Gujarat. In the US, it is often sold under the name of "chai" or "chai tea", as a way of differentiating it from other types of teas sold in the US.
In Mexican cuisine, cloves are best known as "clavos de olor", and often used together with cumin and cinnamon.
In Vietnamese cuisine, cloves are often used to season the broth of Phở.
Due to the Indonesian influence, the use of cloves is widespread in the Netherlands. Cloves are used in cheeses, often in combination with cumin. Cloves are an essential ingredient for making Dutch speculaas. Furthermore, cloves are used in traditional Dutch stews like hachee.
Non-culinary usesThe spice is used in a type of cigarette called kretek in Indonesia. Kreteks 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. However, they are still sold in similar form, re-labeled as "filtered clove cigars."
Cloves are also an important incense material in Chinese and Japanese culture. And clove essence is commonly used in the production of many perfumes.
During Christmas, it is a tradition in some European countries to make pomanders from cloves and oranges to hang around the house. This spreads a nice scent throughout the house and acts as holiday decorations.
Cloves are often used as incense in the Jewish practice called Havdala
Clove oil anesthesia and overdose is considered a humane method for euthanizing fish.
Medicinal and nostrumsCloves 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. The use of a clove in toothache is also said to decrease pain. It also helps to decrease infection in the teeth due to its antiseptic properties. Clove oil, applied to a cavity in a decayed tooth, 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. This would translate to hypochlorhydria. Clove oil is used in various skin disorders like acne, pimples etc. It is also used in severe burns, skin irritations and to reduce the sensitiveness of skin.
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.
In West Africa, the Yorubas use cloves infused in water as a treatment for stomach upsets, vomiting and diarrhea. The infusion is called Ogun Jedi-jedi.
Western studies have supported the use of cloves and clove oil for dental pain. However, 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 anti-herpesvirus properties.
The buds have anti-oxidant properties.
HistoryUntil 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. Nevertheless, they found their way west to the Middle East and Europe well before the first century AD. Archeologists found cloves within a ceramic vessel in Syria along with evidence dating the find to within a few years of 1721 BC.
Cloves, along with nutmeg and pepper, were highly prized in Roman times, and Pliny the Elder once famously complained that "there is no year in which India does not drain the Roman Empire of fifty million sesterces." Cloves were traded by Arabs during the Middle Ages in the profitable Indian Ocean trade. In the late fifteenth century, Portugal took over the Indian Ocean trade, including cloves, due to the Treaty of Tordesillas with Spain and a separate treaty with the sultan of Ternate. The Portuguese brought large quantities of cloves to Europe, mainly from the Maluku Islands. Clove was then one of the most valuable spices, a kg costing around 7 g of gold.
The high value of cloves and other spices drove Spain to seek new routes to the Maluku Islands, which would not be seen as trespassing on the Portuguese domain in the Indian Ocean. Ferdinand and Isabella of Spain sponsored the unsuccessful voyages of Christopher Columbus, and their grandson Charles V sponsored the voyage of Ferdinand Magellan. The fleet led by Magellan reached the Maluku Islands after his death, and the Spanish were successful in briefly capturing this trade from the Portuguese. The trade later became dominated by the Dutch in the seventeenth century. With great difficulty the French succeeded in introducing the clove tree into Mauritius in the year 1770. Subsequently, their cultivation was introduced into Guiana, Brazil, most of the West Indies, and Zanzibar.
In Britain in the seventeenth and eighteenth centuries, cloves were worth at least their weight in gold, due to the high price of importing them.
Active compoundsEugenol 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, gallotannic acid, methyl salicylate (painkiller); the flavonoids eugenin, kaempferol, rhamnetin, and eugenitin; triterpenoids like oleanolic acid, stigmasterol and campesterol; and several sesquiterpenes.
Eugenol has pronounced antiseptic and anaesthetic properties. Of the dried buds, 15 - 20 percent is essential oils, and the majority of this is eugenol. A kilogram (2.2 lbs) of dried buds yields approximately 150 ml (1/4 of pint) of eugenol.
Eugenol can be toxic in relatively small quantities—as low as 5 ml.