Cloves (Syzygium aromaticum, syn. Eugenia aromaticum or Eugenia caryophyllata  Thunb., Diss.1.1788)
Eugenia aromatica  (L.)Baill.,
Nomenclature-
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 syn. (Eugenia caryophyllata)
 
Cloves are the aromatic dried flower buds of a tree in the family Myrtaceae.
Native to the spice islands of Indonesia, cloves are now grown in other countries like Sri Lanka, India, Brazil, West Indies, Madagascar to name a few.

The name of the clove plant is Syzygium aromaticum, a tropical tree and the clove so-called being a derivative of the Latin word ‘clavus’ meaning nail, for its nail-like appearance. The immature unopened flower buds of this tropical tree is known as cloves and when they are fresh, are pink in colour and when dried, they turn brown.

The best form of cloves is in its whole state. Powdered cloves lose their flavour quickly and are best to grind it as and when required.

In cuisine, ground cloves give a strong flavour so they should be used sparingly. Ham and pork are often studded with cloves. Cloves are used as an ingredient in curry powders and pickling spices and are an essential ingredient for Worcestershire sauce. Cloves are a favourite spice for flavouring meat and rice dishes. In India, cloves are the main ingredient for their Masala tea or spice tea. Otherworld cuisines too use cloves as a key ingredient.

There is also a non – culinary usage where it is used in a spicy cigarette called kretek in Indonesia. Many European and Asian countries too, use these kreteks. It is believed that eugenol which is a component of cloves reduces the harshness of the tobacco in a manner similar to that of menthol.

In Chinese and Japanese culture it is used as incense. Oranges and lemons are studded with cloves and left around the house for decoration as well as fragrance. Clove oil is also used in the manufacture of perfumes, toothpaste,  soap, cosmetics etc.

Cloves are also known for its medicinal properties. Clove oil is well known for its efficacy in treating toothaches. Clove oil is also used in aromatherapy. For digestive problems, warmed clove oil is rubbed over the stomach area for stimulation. Skin irritations, severe burns, skin sensitivity, acne have benefitted from the use of clove oil.

As with all things, there is also a flip side. Clove oil should not be used for problems of the mouth in children. They could cause much damage to the system.  A major cause for concern is that clove oil slows down the process of blood clotting. This is due to the chemical eugenol that’s present in cloves. It is recommended that for those undergoing surgery the use of cloves should be stopped for at least 2 weeks before surgery. Clove oil should also not be used with medication that inhibits the thickening of the blood.

Technical Details
Clove is derived from the Latin word ‘clavus ‘meaning nail. This is because the head of the clove resembles the head of the nail and then it tapers to a point. The clove is the immature unopened flower of a tropical evergreen of the Myrtaceae family. Indonesia is the native homeland of cloves but is also now grown in Madagascar, Zanzibar, Brazil, Sri Lanka (Ceylon ), India and Pakistan.

The clove tree grows to a height of 8 – 12 m. The flowers appear in clusters at the end of the trees’ branches. The unopened buds when harvested are pink in colour and then turns brown when it is dried. The bud consists of a long calyx that separate into 4 sepals and the unopened petals form a ball in the centre. They are harvested when they are normally 1.5 – 2 cm long. Cloves are a tropical spice that grows best near the sea. Rainfall for the year should be at least 60 inches and there should be sufficient dry season to harvest and dry the cloves.

Cloves should always be bought in their whole form. Powdered cloves lose their pungency very fast. Cloves are best stored in tightly-sealed containers and placed in cool and dry places.

Eugenol is the main constituent of clove oil and is responsible for the fragrance of cloves. However, eugenol is known for slowing down the process of blood clotting and care should be taken when using it in excessive amounts.

Cloves and their oil should not be used in excess of normal amounts, as it will result in plenty of adverse health problems. If used in moderation, it is good for skin ailments such as acne and when it is rubbed over the stomach area for stimulation of the digestive tract. In dentistry too, overuse could result in damage to the tooth pulp, gums and mucous membranes.

Clove cigarettes too can cause health problems, such as respiratory problems and lung infections.  They are more deadly than normal cigarettes and in addition to the normal risks of smoking, inhaling clove smoke could lead to a build-up of fluid in the lungs or cause severe pneumonia. Never give children clove oil. It will damage their lungs and can cause severe breathing problems.

Propagation & Harvesting

Cloves flourish in tropical climates. It should have adequate periods of rainfall and dry seasons and the soil should have good drainage. Cloves cannot tolerate waterlogged conditions. The best area for the growth of clove trees is the areas closest to the sea.

There are two methods of propagating cloves. One is by planting cuttings and the other is by planting the seeds. For this method, the seeds are allowed to ripen on the tree and allowed to fall on their own. These seeds are gathered and then planted as it is or sometimes they are soaked in water overnight to remove the outer covering and then planted. Seeds are planted during spring to propagate. If all conditions for the growth of clove trees are satisfied then the trees begin to flower within five to seven years.

 Harvesting Periods

The harvest of Cloves starts from about mid-December and continues till the end of February.

They are harvested by hand, only when the flower buds turn pink. Cloves are ripe for harvesting when the lower part of the flower turns from green to purple. The flowers of the clove tree are found in clusters. After picking the buds they are separated from the clusters and left to dry in the sun. When dried they turn a dark brown. 

In most places, the floral buds are harvested twice a year. Care should be taken that harvesting should take place at the correct time. If harvested too early it loses its aroma and strength.

The weight of dried cloves is normally a third of the weight of fresh cloves.  A good harvest of cloves would be about 10 Kg of dried cloves per tree per year. It has been found that a good harvest is normally followed by two poor harvests.

The time taken for a normal harvest is about four days for each big tree using at least 3 labourers. Clove harvesting requires skilled labour. The shortage of skilled labour can impair the quality of the harvested cloves to a great extent.  

All the trees on a clove plantation have to be harvested simultaneously. If not the buds will bloom resulting in a loss. In addition to the four days for harvesting, a further three days is necessary for drying the cloves and skill is necessary to watch it achieves the right colour.
 
Available Forms
Cloves are available in 3 forms. It is available in the form of whole cloves, clove oil and clove powder.

WHOLE CLOVES
Whole cloves are the unopened buds of the flowers of the clove tree. The buds are normally handpicked and sun-dried.

When the dried cloves are sorted they are categorized into 4 grades.

Whole cloves are widely used in the cuisine of many countries and are used to flavour soups, salads, meats and rice dishes.

Sometimes it is used as a decoration and a deodorizer when oranges and lemons are stuck with cloves and hung around the house.

CLOVE OIL
Clove oil is a product of the clove plant. It could be categorized into 3 forms of oil

1. Bud Oil - This is obtained from the buds of the clove flower and contains about 60 – 90 % Eugenol and other constituents. Eugenol is a predominant constituent of Clove oil and is an important ingredient of clove based products.
2. Leaf Oil - As the name suggests, this oil is obtained from the leaves of the clove plant. This consists of approx. 82- 88% eugenol.
3. Stem Oil - This oil is obtained from the twigs of the clove tree and consists of about 90 % - 95% Eugenol.

Eugenol is the main ingredient of clove oil and due to its efficacy as an analgesic and antiseptic, it is used widely in dentistry, in the manufacture of toothpaste and mouthwashes. It can be purchased over the counter. Clove oil is also used in the manufacture of toiletries.

Clove oil is also used to flavour foods and in medicine, it is used in the treatment of influenza. It is also an aromatherapy oil. The main areas that produce clove oil are Madagascar and Indonesia.
Clove oil is problem-free if used in small quantities but if it is ingested or injected in sufficient quantities it could prove to be fatal.

Uses Of Clove Oil In Medicine - the oil is very popular for treating toothache. Cloves are also used in treating indigestion, diarrhoea, hernia and fungal infection.

In Ayurvedic Medicinal uses, cloves have gained a place in treating respiratory and digestive problems.

CLOVE POWDER
The unopened buds of the clove tree are known as cloves. After harvest, it is dried in the sun for about 3/4 days. These dried cloves are then ground into powder form. It is recommended that when using cloves it is best to buy whole cloves because clove powder tends to lose its aroma and strength rather quickly.

As a digestive aid, the recommended dosage of clove powder is about 1 tsp added to a cup of boiling water. Drink thrice a day.

Clove powder should only be used under medical care if used in large amounts. Due to the effect of eugenol being unclear on cell growth, it is best not to give it to cancer patients.

In normal amounts, it is considered nontoxic for normally healthy people.

Next Chapter: Ginger