PEPPER - a spice

Piper nigrum L. (Piperaceae).

Given its scientific name by Carolus Linnaeus in 1753; black pepper was described as coming from India.

Native to India, usually in montane forests.

Life form: herbaceous to slightly woody vine.

Parts used: seeds used as seasoning.

Ploidy level: diploid.

Wild relatives

Spices are very important in the history of food, trade and medicine. Pepper was so essential in Roman times that much of the gold extracted from (Roman) Spain ended up in India; pepper was valued as highly as its weight in gold. When Europeans reached the Malabar Coast of India, they found India very much richer than they had been led to believe. Merchants trying to break the Arab pepper monopoly by reaching the Spice Islands from the west instead of overland, financed Christopher Columbus, which led to the discovery of the New World. Other spices have all been important at different times, and have all been recommended by apothecaries, physicians and medicine men in the last millennium to alleviate every kind of condition. Spices are still exceptionally expensive, in comparison to other plants that have become gradually less expensive since 1500. Only vanilla has been successfully synthesised.

The definition of a spice is somewhat vague. Here we distinguish spices and herbs - spices are usually of tropical/subtropical origin, and include seeds, roots and bark; herbs are the fresh or dried green parts of herbaceous plants, usually temperate in origin. The spices covered in detail here are cardamom, ginger, turmeric, vanilla and pepper.

Elettaria cardamomum (L.) Maton (cardamom) is a herbaceous perennial native to the moist evergreen forests of southern India. Unlike ginger and turmeric, which are also members of the family Zingiberaceae, the useful part of cardamom is the seed pod, which can also be used as a perfume.

Zingiber officinale Roscoe (ginger) is a herbaceous perennial probably native to South-East Asia and unknown in the wild state. The ginger family, Zingiberaceae, also contains some important spices. All members of this family are large tropical herbs and the spices are usually derived from the fleshy rhizomes, or horizontal stems.

Curcuma longa L. is generally accepted as the correct name for turmeric, although it has also been known as Curcuma domestica Valeton. Turmeric is a sterile triploid native to southern India and South-East Asia, and no longer found in a truly wild state. The wild progenitors of turmeric are thought to be Curcuma aromatica Salisb., a wild diploid found in India and Sri Lanka, and an as yet unknown closely related tetraploid.

Vanilla planifolia Jacks. ex Andrews (vanilla) is a member of the family Orchidaceae. It is indigenous to south-eastern Mexico, Guatemala and other parts of Central and South America, growing wild as an epiphyte in tropical lowland forests. Two other species of vanilla are less widely cultivated - Vanilla pompona Schiede is a West Indian vanilla found wild in Central America, northern South America and the Lesser Antilles that resembles Vanilla planifolia but with larger leaves and flowers, more compact pods and more thickset flowers; Vanilla tahitensis J.W. Moore (Tahitian vanilla), is native to Tahiti where, in addition to Hawaii, it is cultivated. This species is more fragile than Vanilla planifolia.

Piper nigrum L. (pepper) is a tropical plant of the large family Piperaceae. It is native to the Western Ghats of India and still grows wild in the hills of Assam and north Burma. It grows typically on forest-clad slopes in a monsoon climate with 30-40 cm of rain per year. The genus Piper is found in both the Old and New World tropics; the closest relatives of black pepper are also found in India. Species of Piper are important medicinals in both hemispheres, and the root of Piper methysticum G. Forst. is the source of the hallucinogen kava kava. Also given the common name pepper are species from the genus Capsicum of the potato-nightshade family, Solanaceae. Capsicum is not related to Piper nigrum, but the fruits are used in a similar way, to season food. The genus Capsicum has a wide variety of fleshy-fruited peppers grown as herbaceous annuals in a variety of colours including red, green and yellow. They are a valuable source of vitamins A and C.

Cinnamomum verum J. Presl (cinnamon) is an evergreen bushy tree of the laurel family (Lauraceae) native to Sri Lanka, the Malabar Coast of India and Myanmar (Burma). Strips of bark are dried to make commercial cinnamon. It grows wild in Sri Lanka and south-western India to approximately 2000 m, but grows better in the lowlands. There are plantations in Sri Lanka, Madagascar, the Seychelles and southern India, but much is still harvested from the wild.

Syzygium aromaticum (L.) Merrill & Perry (clove) is a member of the family Myrtaceae indigenous to the small volcanic islands of the Moluccas in Indonesia. Other species of the genus Syzygium are cultivated from their edible fruits. Cloves are the unopened flower buds of this species. Being highly aromatic, the family Myrtaceae also contains some important spices from both the New and Old World tropics. It also includes plants such as Eucalyptus (eucalypts) and Myrtus (myrtles).

Myristica fragrans Houtt. is a tropical dioecious evergreen tree in the family Myristicaceae that produces both nutmeg and mace. The tree is also native to the Islands of the Moluccas, but is rarely found wild. Its closest relative is found in nearby New Guinea. Nutmeg is the seed of Myristica while mace is the fleshy red aril that covers the seed and attracts birds, which eat the fruit. The name nutmeg is also applied in different countries to other fruits or seeds unrelated to the true nutmeg.

Many economically important spices and herbs also belong to the carrot family Apiaceae. These are primarily of European origin and include Carum carvi L. (caraway), which originated in Europe and western Asia; Coriandrum sativum L. (coriander), a Mediterranean native; and Cuminum cyminum L. (cumin) originating in the Levant. The seeds of all these species are used as seasoning and the leaves of many are used as herbs.

Origins of cultivation

Cardamom

Most of the cardamom plants cultivated before 1800 were wild plants that had been selectively thinned. Cardamom was used in Roman perfumes and increased demand from the perfume industry led to it being specially cultivated. Cultivation is still concentrated within its natural distribution range and is limited to a few countries, mainly southern India and Sri Lanka, although there is now significant production in Guatemala. There were unsuccessful attempts in the 19th century to grow cardamom in Singapore and Penang. The vernacular name can be misleading and 'cardamom' from Thailand and neighbouring countries is probably of the related genus Amouma.

Ginger

The name is derived from the Greek 'zingiberis', which comes from its Sanskrit name 'singabera'. Ginger was first used in India and China in the 2nd millennium BC. By the 1st century AD, traders had taken the spice to the Mediterranean. By the late Middle Ages, a pound of ginger was valued as highly as the cost of a sheep.

Turmeric

Turmeric was native to south or South-East Asia, and probably domesticated there. The cultigen, a sterile triploid that does not fruit, appears to have emerged from a long period of selection from wild ancestors, with subsequent cultivation. Turmeric is mentioned in early Sanskrit writings of 300-500 AD.

Vanilla

Vanilla was native to the Caribbean, both the Mexican mainland and the islands. When the Spaniards arrived, it was noted as an accompaniment to unsweetened chocolate as a drink. The common name is derived from the Spanish for sheath - the pods look like the sheathed swords of the Spanish explorers.

The pods are large, 15-25 cm long and up to 1.5-2 cm in diameter, although the selected and cultivated strains have larger pods than wild plants that can still be seen in the forests of Mexico. It is not known whether, in the early 1500s, the Aztecs collected vanilla pods from the jungle or encouraged plants brought in to cultivation.

Black pepper

Pepper has been grown on the west coast of India, centred on Malabar, since at least 500 BC. Hindu colonists carried pepper seedlings from India and by 100 BC they were planted in South-East Asia. Modern production areas include Indonesia and Thailand. Expatriate Chinese have been growing pepper in Borneo for about 300 years. The Dutch established large pepper 'gardens' in Java and Sumatra in the 16th and 17th centuries, as did the French later in Cambodia.

Cinnamon

Cinnamon is a very ancient spice, used in Egypt as early as the 2nd millennium BC. The cinnamon of early usage would definitely have come from harvesting wild trees, as illustrated in Paul Hermann's 1680 account of the botany of the region; today, it is primarily cultivated. The Dutch established the first plantations in Sri Lanka, and began commercial production in 1770.

Cloves

Cultivation of the clove began about 2000 years ago in the Indonesian Moluccas Islands. In the 17th century, the Dutch eradicated the cultivation of cloves from all but two islands, Amboina and Ternate, in order to keep supplies scarce and thus protect their trade monopoly.

Nutmeg and mace

Nutmeg and mace were first used in South-East Asia during the centuries before Christ, but were only introduced into Europe in the 5th century. Fruits were collected from the wild before the Dutch started cultivation and production in the 17th century. Nowadays the species is not known in a truly wild state.

Early uses

Cardamom

The words 'cardamomum' and 'amomum' were used by the Greeks and Romans for certain spices brought from the East, mentioned by Theophrastus in the 4th century BC and Dioscorides five centuries later. The Romans used cardamom in perfumery. By 1000 AD cardamom was being traded from India westwards to Europe. Barbosa of Portugal mentions cardamom as a product of the Malabar Coast in 1514.

Ginger

Ginger has been used as a Western culinary and medicinal herb for at least 2000 years. Ginger was known in Europe no later than the first century AD and was mentioned by both Dioscorides and Pliny. The Elizabethan herbalist Nicolas Culpeper mentions ginger in his herbal of 1653 as profitable for old men - it was said to heat the joints and was therefore useful against gout. It was traditionally used to warm the stomach, aid digestion and dispel chills. Henry VIII appears to have valued its medicinal properties (possibly against venereal disease). In the 18th century it was added to remedies to modify their action and reduce irritant effects on the stomach and in China it is still used in this way today, to reduce the toxicity of some other herbs. Ginger oil has been used in both East and West for 400 years. In France it is still prescribed in drop doses on sugar lumps for flatulence and fevers and to stimulate the appetite. It is also an important resource in Chinese cuisine.

Turmeric

Turmeric is used in India as a dye in the same way as the much more expensive saffron. In Sanskrit and other languages the name turmeric means 'yellow', a sacred colour. Turmeric was used to paint the body for ceremonies relating to birth, marriage and death, as well as in agriculture. Available as rhizomes and powder, is still an auspicious article of religious observance in Hindu households and its use in ancient ceremonials spread in early times to Oceania. The use of turmeric in domestic rites outside India, especially in the Celebes and other islands, is an indication of antiquity. The Betsileo people of Madagascar used turmeric so it was most likely to be an introduction there, possibly by the Malayo-Polynesian people. In Biblical times in the Levant it was used as a perfume as well as a spice. In the Middle Ages it was called 'Indian saffron' because it had an orange-yellow colour. It later became an important dye in southern Asia and Europe, before the discovery and mass production of aniline dyes.

Vanilla

In 1520, Montezuma gave Hernándo Cortés chocolate flavoured with vanilla. As a result, pods were sent to Spain and, when Cortés was sent to Mexico in the 1570s, he sent Montezuma an illustrated account of the vanilla plant. This was published in 1651. William Dampier observed vanilla growing in southern Mexico in 1676 and in Costa Rica in 1681.

Black pepper

Black pepper was mentioned by Theophrastus (372-287 BC), who reported that it was used by the Greeks and Romans. It was one of the first important trading items between the East and Europe and long before the Middle Ages it had assumed great economic importance. It was used to make insipid food palatable and as a preservative when curing meats. Mixed with other spices, it helped to disguise the smell of rancid food. Pepper was also used in medicine, as a carminative and febrifuge. Peppercorns were once extremely expensive and rents and tributes were often paid in peppercorns, hence the term 'peppercorn rent', which has now come to mean an insignificant sum. Every sailor on the ship the Mary Rose carried his own bag of peppercorns.

Cinnamon

Cinnamon was another spice as valuable as gold. In Egypt it was used in embalming and witchcraft, and it appears to have reached Europe by the 5th century BC and was known to Herodotus. It was brought from India and Ceylon (now Sri Lanka) to southern Arabia, a centre of the spice trade. Arab traders concealed the true source of spices to protect their profits. In medieval Europe cinnamon was used in religious rites and as a flavouring. The Portuguese occupied Ceylon in 1536, largely to control the cinnamon trade and in the 16th century extracted a tribute of over 100 tonnes of cinnamon bark annually from the Singhalese king. They retained a monopoly until conquered by the Dutch in 1656. Cinnamon was one of the most profitable spices for the Dutch East India Company, which controlled the world supply until the British took Ceylon in 1796 and maintained their own monopoly until 1833. Annual production at the beginning of the 19th century was about 250 tonnes.

Cloves

Cloves have been used in the Orient, particularly India and China, for over 2000 years as a spice, to alleviate tooth pain and counter halitosis. In the third century BC court officials in China used them to sweeten their breath before meeting the emperor. In Persia and China cloves were considered to be an aphrodisiac.

Nutmeg and mace

These important spices do not appear to have been known to the Greeks and Romans, but there is a record of nutmeg in Constantinople about 540 AD, imported via the Silk Route. Nutmeg became important around 1600, and as expensive as other commercial spices in the Western world. The Dutch plotted to keep prices high while the English and French tried to obtain fertile seeds for transplanting elsewhere. Nutmeg, dipped in lime to prevent germination, was first brought to Europe by the Portuguese from the Banda Islands (Indonesia) around 1512 and gained a reputation as a cure-all. It was important in cookery and for medicinal purposes for the Chinese, Indian and Arab cultures; the Chinese had used it since the 7th century for stomach problems. It was soon discovered that it was hallucinogenic - nutmeg eaters who overindulged became 'deliriously inebriated'. It was once taken (wrongly) to produce abortions and was also claimed to be a cure for the plague.

Transfer and spread

Cardamom

Cardamom could be found growing in the garden of the King of Babylon as early as 721 BC. The ancient Greeks and Romans used it in perfumes, and it is believed to have reached Europe in the 13th century. Today, it is mostly cultivated in India, Nepal, Sri Lanka, Thailand, Mexico and Guatemala.

Ginger

Grown in India and China from ancient times, it was traded in Germany and France in the 9th century and in England in the 10th century; by the 13th and 14th centuries it was nearly as common in trade as pepper. Marco Polo saw the plant growing in China, Sumatra and Malabar in 1280 and preserved ginger from China was imported into Europe as a sweetmeat early in the Middle Ages. The Arabs took the plant from India to East Africa in the 13th century and the Portuguese took it to West Africa and other parts of the tropics in the 16th century. Portuguese supplies came from São Tomé, and island state west of Gabon, thus cutting out India, which had been a major producer before 1500. As the living rhizomes are easy to transport and soon root to produce new plants, ginger was quickly planted throughout the tropics. The Spaniards took the plant to Mexico soon after the conquest and to Jamaica, from where over 1000 tonnes of ginger were exported to Spain in 1547. Jamaica, which was British after 1660, continued to be a major producer and exporter of high quality ginger and still is today.

Turmeric

Originally grown in India, it is now cultivated extensively. Turmeric was mentioned in Sanskrit writings of the 4th and 5th centuries AD and it appears to have reached China before the 7th century. Marco Polo records it as being at Koncha in China in 1280. Turmeric spread throughout the East Indies and was later taken east across the Pacific by Polynesians, as far as Hawaii. It reached East Africa in the 8th century and West Africa in the 13th century, although it was only used there as a dye. Captain Edwards introduced turmeric to Jamaica in 1783, where it has now naturalised. It is now widely distributed throughout the tropics but its cultivation as a spice is largely confined to India, South-East Asia and the East Indies, where conditions are most suitable.

Vanilla

The pods of vanilla were first introduced into Europe as a trading product in the 16th century, and were then taken to England. A plant had flowered in Charles Greville's collection at Paddington by 1807 and it was Greville who supplied cuttings to the botanic gardens in Paris and Antwerp. Of the two plants that went from Antwerp to Buitenzorg in Java in 1819, only one survived the journey. Vanilla was first taken to Réunion in 1793.

The vanilla plant grew well in the tropics of the Old World but because there were no pollinators, no fruit set. It was not until 1836 in Liège that Charles Morren was able to produce pods by artificial pollination and in 1841 Edmond Albius, a former slave in Réunion, discovered a practical method of artificial pollination (still used today). This method stimulated vanilla cultivation in the wake of a sugar cane crop failure on Réunion in 1849-56. It was then that commercial production became possible in the eastern hemisphere.

Vanilla cultivation was introduced into Java in 1846 and planting material was sent from Réunion to Mauritius in 1827, to Madagascar about 1840 and to the Seychelles in 1866. Plants were taken from Manila to Tahiti in 1848 and to the Comoro Islands in 1893. Vanilla was cultivated as early as 1839 in Martinique in the West Indies and probably about the same time in Guadeloupe. The Malagasy Republic is now by far the largest producer, although Mexico was the first commercial producer, and Mexican vanilla is still of the highest quality, better even than the synthetic product.

Black pepper

In Ancient Rome pepper was exchanged, pound for pound, with gold dust. Black pepper was probably taken by Hindu colonists to Java around 100 BC and in 600 AD; pepper was recorded as being traded between Java and China in 1200 AD. Marco Polo reported pepper in Malaysia in 1280. Arabs traded pepper from the Malabar coast of India and later from Java to Yemen and from there to Alexandria and Venice. There was a Guild of Pepperers in London as early as 1180.

It was the search for the source of pepper that inspired Columbus on his voyages to find an alternative route to the East in 1492, resulting in the discovery of the Americas. Vasco da Gama travelled around Africa in 1498 in search of the Spice Islands and thereafter the trade monopoly was controlled by the Portuguese until the 17th century. It was during Portuguese control of the trade that Malacca and Goa became major pepper emporiums. The Dutch captured much of the trade from the Portuguese but they never achieved as much control over pepper as they did over nutmeg or cloves.

Pepper was grown in Ceylon in the 1700s and later in Cambodia; in the 1800s the British organised plantings in Penang, Singapore and parts of Malaya. During the 20th century, the growing of pepper spread to many tropical countries, such as Brazil and the Malagasy Republic. Although labour-intensive, it is an easy crop to grow and its high price before the 1600s was due to an Arab monopoly, later replicated in Europe by the Venetians.

Cinnamon

Cinnamon was introduced into Java in 1825, and cultivation began in southern India, the Seychelles, Madagascar and Brazil. It is now cultivated in South America and the West Indies, but Ceylon still produces the best cinnamon.

Cloves

In the early 16th century the Portuguese discovered and occupied the Spice Islands in the Moluccas and had a monopoly on the trade in cloves. However, the Dutch captured Amboyna in 1605 and controlled the clove trade for two centuries. The French managed to smuggle clove plants and seeds from Amboyna to the French islands of Mauritius and Réunion in 1772, and plants were taken to Cayenne in the New World in 1789 and from there introduced to Dominica, Martinique and other French West Indian islands; the Dutch monopoly was broken. At the beginning of the 19th century the East India Company took cloves (and nutmeg) from the Moluccas to Penang. Extensive plantings were made in Penang in the 1820s but the crop was not as successful in Singapore and Malacca as it had been in Amboyna.

A Zanzibar Arab took cloves from Mauritius to Zanzibar in 1818 where they flourished. The Sultan, realising their worth, confiscated the land of plantation owners if they did not plant cloves, with the result that more than half of the area of Zanzibar is now devoted to cultivating cloves. When hurricanes destroyed the clove plantations in Mauritius and Réunion, Zanzibar became the leading supplier; it still retains this position. Cloves were introduced from Mauritius to the island of Sainte-Marie off the coast of Madagascar in 1827, but extensive production did not begin there until 1895 and in 1900 was extended to mainland Madagascar. If the wind is coming from the right direction, the cloves can be smelt at sea off Zanzibar.

Nutmeg and mace

Nutmeg and mace reached India by about 1100 and in all probability went to Europe soon afterwards. By the 1300s they were well known spices in Europe, but very expensive. They came from the Moluccas via Java and India and, as with other spices, the Arab traders hid the true source and this only became known when the Portuguese saw the trees growing in Banda and Amboyna in 1512. The Portuguese retained power in the islands until the beginning of the 1600s when the Dutch took over. The Dutch held vast stocks of the spices in order to maintain high prices and large quantities were burnt in Amsterdam in 1760. The Dutch held the monopoly for over 250 years.

In 1772, the French successfully introduced nutmeg and mace to Mauritius and French Guiana, but the Dutch monopoly was more convincingly broken when Christopher Smith of the British East India Company collected 70,000 nutmeg plants which he took to Penang, Calcutta and Madras, with a few going to the Royal Botanic Gardens, Kew. The plants flourished in the East until there was a dual outbreak of beetles and disease in 1859-64. In 1843 nutmeg trees were introduced into the island of Grenada in the West Indies, which, together with Indonesia, is still one of the main producers.

Agriculture

Cardamom

Cardamom thrives in moist, shady areas, particularly in the Cardamom Hills, the south-eastern Kerala state of southern India. This area also produces tea, coffee, teak and bamboo. In India, cardamom is grown at a height of 750-12,500 m and, in Sri Lanka, above 1000 m. They require an annual rainfall of 1-1.5 m, temperatures of 10-35ºC and protection from the wind. They are sometimes grown under coffee bushes or areca palms. In Guatemala, they are interplanted with coffee.

Cardamon plants are cross-pollinated by bees, and can be propagated by seed, by rhizome or vegetative cuttings. In natural conditions, seeds can lie dormant for considerable periods of time. Clonal propagation permits the planting of high-yielding selections; these provide earlier yields with shorter lives. At three to four months old, nursery seedlings are transplanted 15-45 cm apart; at one to two years of age, they can be transplanted into the field. Aftercare involves weeding, mulching and removal of old stems. Cardamom starts bearing fruit about three years after planting into the field, and lasts for 10-15 years. A whole fruit contains some 15-20 seeds, and are clipped from the stems just before full maturity to prevent them splitting during drying. Once cleaned and dried in the sun or heated in a curing chamber, the capsules are rubbed and winnowed to remove pedicels, calyces and foreign matter. The average annual yield of dried capsules is about 100-250 kg/hectare.

The most serious pest threat to cardamom are thrips (Taeniothrips cardamomi Remak.), which cause scabbing of the fruits and may cause flowers not to set. Shoot borers, Conogethes punctiferalis (Guenée), attack the stem and fruits, and a swarming caterpillar, Eupterote mollifera Wlk., can defoliate whole clumps. Monkeys, rats, porcupines, wild pigs, elephants and birds can also cause considerable damage.

Ginger

Ginger is grown over more diverse conditions than most other tropical spices, anywhere from from sea level to 1500 m. It requires an annual rainfall of 1.5 m or more, with a dry season and high temperatures for at least part of the year. It thrives on medium loam soils, with a good supply of humus but no waterlogging. Each centre of production tends to produce a distinctive type of ginger, possibly because of sensitivity to local climate and soil conditions.

The plant is propagated by root cuttings. After washing and drying, the sets can be stored in covered pits before planting. This method has been in common practice for so long that the plants no longer go to seed.

The leafy stems of ginger grow to about 1 m in height, with leaves 15-30 cm long and flowers on cone-like spikes. Ginger is often the first crop grown on newly cleared land. In Jamaica, it is typically grown on smallholdings; in tropical Australia, it is also grown on small individual acreages. Ginger is an exhausting crop, and benefits greatly from the addition of manure. The first shoots appear above ground after about ten days, and weeds can be controlled by herbicides. Harvesting is done 9-10 months after planting, when the leaves begin to yellow. For preserved ginger, the rhizomes are harvested before they are fully mature. Mature ginger is fibrous, more pungent and better suited for dried or ground ginger. The crop is generally harvested manually, but in Queensland planting and harvesting is mechanised. Yields per hectare vary according to area: 5-7.5 tonnes/ha of dried ginger in Jamaica, 7.5-10 tonnes/ha in India and 10-25 tonnes/ha in Australia. Harvesting is done by lifting the rhizomes, cleaning them and drying them in the sun.

Ginger is attacked by various kinds of rot. In Australia, root-knot nematodes (Meloidogyne spp.) attack the crop and cause serious losses unless controlled. Between 20 and 30% of a crop needs to be retained for propagation.

Turmeric

Turmeric is a perennial herb with tufted leaves. It is usually grown in areas with an annual rainfall of 1-2 m. If the rainfall is less than this, crops must be irrigated. Cultivation now extends into wetter areas with over 2 m rainfall, and turmeric can be grown up to an altitude of 2000 m in the Himalayan foothills. It thrives on loamy or alluvial loose, friable, fertile soils, and cannot tolerate waterlogging. Although shade can reduce yield, turmeric is often grown in rotation with rice or sugar cane and is sometimes mixed with vegetable crops. The crop is propagated by rhizomes with one or two buds planted 5-7.5 cm deep, 30-45 cm apart and often on ridges. Some 1500-1800 kg of sets are needed for 1 hectare. Turmeric is often grown as an irrigated garden crop, and responds well to the addition of nitrogen and potash manures. In India, the crop is planted in April or May, and leaves appear above ground in four weeks. The crop can be harvested after 9-10 months when the lower leaves turn yellow. Rhizomes are usually dug up manually, and yields range from 13 to 25 tonnes of green or raw turmeric per hectare. The most serious pests are the fungal leaf blotch (Taphrina macalans Butl.) and a shoot-boring caterpillar (Conogethes punctiferalis (Guenée)) that can kill the shoots.

Vanilla

The principal source of natural commercial vanilla is a stout, scandent, terrestrial or epiphytic orchid growing in the tropics of both hemispheres. In the wild state, the vanilla vines climb up trees in wet lowland forests. It thrives in hot, moist climates with temperatures between 21-32ºC and an annual rainfall of 2 -2.5 m, followed by two drier months to induce flowering. Too much rainfall during ripening is harmful to the plant, but areas with prolonged dry seasons should also be avoided.

The vines grow well on gently sloping land with a light and friable soil, adequate drainage, and a thick surface of humus or mulch. Vanilla cannot tolerate waterlogging or stagnant water, but partial shade from shrubs or trees up which the vines can grow is desirable. In cultivation, the vines are trained to a height of 10-15 m to enable hand pollination and harvesting; for commercial purposes, harvesting is done before the vanilla is quite ripe. The flower's anatomy makes self-pollination impossible. In Mexico and Central America, the flower is pollinated by stingless bees of the genus Melipona. Hummingbirds may also act as pollinators. In Mexico, hand pollination is carried out whereas, in Puerto Rico, only 1% of vanilla plants are hand pollinated.

The flowers open only once a year, over a period of three months. They open early in the morning, and can be pollinated for only a few hours. Fruit set is highest when pollinated early on a sunny morning. If fertilisation is successful, the flowers remain on the rachis; and if unsuccessful, they drop off in two or three days. The crop can be controlled by pollinating exactly enough flowers to produce the desired number of fruits. Cross-pollination produces interbreeding between plants. propagation is vegetative, using stem cuttings 90-100 cm long. As a crop, vanilla vines need support and shade from various trees such as coffee, linerica, maize or bananas.

Black pepper

Most cultivars grow in India, the most widely grown Malabar variety being 'Balancotta'. Pepper likes a monsoon climate, usually at lower altitudes. In Sarawak, pepper grows with a high level of rainfall, although plants cannot tolerate waterlogging. It is usually planted in mounds for drainage, but can be grown on a wide variety of soils with a high humus level. Most planting of pepper is from cuttings, but it can be grown from seed; however, cutting sneed shade and seeds are only viable for 7-10 days. When ripe, the fruits turn red; when dried, the fruits turn balck. The weight of 100 peppercorns is roughly 4.5 g. White pepper is black pepper seeds with the skin abraded.

Pepper is a climbing vine, and therefore needs support. Vines can be grown up specially planted shade trees, and are sometimes planted as a secondary crop with coffee. The Chinese devised a method of growing that is now extensively used on the South-East Asian mainland; this consists of growing the pepper up posts, with no shade but clean-weeded and with plenty of manure. These vines are carefully pruned so that the plants do not produce flowers until they are two years old. It takes five to six months from the emergence of a flower spike, and a further four months to ripen the fruits. The first harvest is two to three years after planting, when they have reached the top of the 3 m poles. The entire fruit spike is removed when a few fruits are red, and the rest still yellow or green. The vines are then stripped of all leaves except for the 2-3 terminal leaves on each branch.

Cinnamon

Cultivated cinnamon is grown in Sri Lanka on sandy soils at low altitudes with an average temperature of about 30ºC and an annual rainfall of 220-250 cm. In the Seychelles and Madagascar, the birds disperse the seeds and insects and flies pollinate the flowers. Seeds quickly lose their viability if they are not sown fresh after removal of the pulp. germination takes two to three weeks. After four to five months, seedlings are transplanted; after a further four to five months they are planted in the field. Cinnamon can also be propagated by cuttings of young three-leaved shoots: to reduce the time to harvest, the shoots are layered and the old rootstocks divided.

In planting up forest land for cinnamon cultivation, it is best to leave tall trees at 15 m intervals to provide light shade. The usual spacing is 2 m and the crop is weeded, until these are shaded out by the trees. The stems are harvested when they are 2-3 m high and 5 cm in diameter. They are cut during the rains to ease peeling, and leaves and twigs are trimmed away. Bark is removed by making two longitudinal cuts so that half the circumference of the bark is removed as an entire piece. The best quality cinnamon is obtained from bark from shoots in the centre of the bush and from the middle portion of the shoots. The stump is then pruned for future regeneration.

Cloves

Cloves thrive in the maritime tropics at low altitudes. Continuous humidity is detrimental, which is why clove cultivation was more successful in Penang than Singapore. In the original habitat of the Moluccas, where the trees are semi-wild, the annual rainfall is 220-380 cm with temperatures of 25-35ºC. Dry weather is needed for harvesting and drying the crop.

Cloves grow best in deep, sandy, acid loams. Good drainage is essential as waterlogging would destroy the trees. Shade is desirable in the early stages of growth, and sometimes windbreaks are necessary. The flowers are pollinated by bees, but most flowers fall without setting seed. Cloves are usually propagated by seed. Their viability is short, but germination rates are about 90% in most cases.

Clove clusters are picked by hand when the buds have reached full size, turned pink but not yet opened into flowers. The lower branches are picked from the ground, but higher branches are lashed together to facilitate climbing away from the trunk. Picking fulfils the function of pruning trees. Trees flower for the first time at about six years of age, but only achieve full bearing at about 20 years. Production continues for at least 70-80 years. Bearing varies from year to year, with a bumper crop approximately every four years.

Cloves are usually dried on mats of palm leaves, spread thinly and turned frequently. They are either protected from the rain during this process or dried in a kiln. Drying takes four to seven days, and quicker the drying produces a better the quality of spice. Green cloves left in heaps heat and ferment and have a whitish, mealy appearance. These are known as 'kohker' cloves. Well-dried cloves snap cleanly with a sharp click and weigh about one-third of their green weight. Clove stems are also dried: green stems are approximately one-fifth of the weight of green cloves and, when dried, also give about one-third of their green weight. The average yield of dried cloves per tree is about 2.5 kg but, in good years, it can be as much as 18 kg.

Cloves are divided into three grades:

  • cloves for export for ordinary spice and Indian trade, which includes about 2% of kohker cloves and stems.
  • cloves with the same specification, but with up to 7% kohker cloves, are for the Indonesian market.
  • cloves with up to 20% kohker cloves and stems are confined to exports for the manufacture of clove oil and vanillin.

Termites may damage growing cloves, but the most serious pest is a fungus called Valsa eugenie which attacks young roots and blocks the vessels to the larger roots. This fungus is also know as 'sudden death' because attacked trees die very quickly. There are also several fungal wound pathogens, known as 'dieback', caused by various species within the genera Botryosphaeria, Leptosphaeria and Coniothyrium. Some parasitic plants that can attack clover are species within the genera Cryptosporella (a Malaysian alga), Cephaleuros mycoides (a vine found in Zanzibar) and Cassytha filiformis (dodder).

Nutmeg and mace

Nutmeg is grown on rich volcanic soil found in non-seasonal climates with 220-350 cm of rain and temperatures of 25-35ºC. Cultivation is largely confined to islands in the hot, humid tropics at altitudes of up to 460 m. Nutmegs cannot tolerate waterlogging or excessive drying out of the soil, and shade is best for early growth.

Nutmeg flowers are pollinated by insects. Seeds quickly lose their viability, and should be sown soon after collection. Although seed production yields and even split of each sex, it cannot be determined until trees are five to eight years old. It is standard practice to destroy surplus male trees, leaving roughly one male to 10 female trees. Because the unknown sex of seeds creates difficulties, vegetative propagation by cuttings from a known sex is advantageous; however, only about 10% of cuttings root successfully.

germination from seed takes four to six weeks, and seedlings are transplanted into the field at 15 cm high. They are initially planted 6-7 m apart, and then again to 12 m after the removal of excess male trees. The trees can reach a height of 20 m, and yield fruit eight years after sowing. They reach their full potential after 25 years, bearing fruit for 60 years or more. The fruits are usually harvested after they have dropped to the ground. The average nutmeg tree produces 1500-2000 fruits per year. Its fruit is a pendulous drupe not dissimilar to an apricot and, when fully mature, it splits in two. This split exposes a crimson aril, the mace, surrounding a single shiny brown seed, the nutmeg. The pulp of the fruit is often eaten locally, but has little commercial significance.

Modern context

Cardamom

The spice has a warm, slightly pungent and highly aromatic flavour not dissimilar to camphor. Seeds are used as a seasoning in Asian dishes (especially curries), and also in Scandinavian pastries, breads and cakes. The name cardamom is sometimes given to other similar spices of the ginger family used in African and Asian cuisines, or as commercial adulterants of true cardamoms. In India, cardamom is often used in betel quid; this is made from a chopped nut Areca catchu L. (Arecaceae), mixed with lime and then folded in a leaf of betel pepper Piper betle L. and fastened with a clove. Substantial amounts of cardamom are also imported by the Middle East to be used for flavouring coffee.

India is the largest producer of cardamom, although production has declined since the 1960s when there was a record crop of over 4000 tonnes. This decline is a result of drought and pests. Cardamom is listed in the British and US Pharmacopoeias, which lists it as an aromatic stimulant, carminative and flavouring agent.

Ginger

Ginger is a popular spice with a biting taste. It is usually dried, ground and used to flavour breads, sauces, curry dishes, confections, pickles, ginger beer and ginger ale. It is one of the most widely used spices in Chinese cookery. The fresh rhizome can be sliced or chopped and used in cooking. Ginger was once used for spicing wines and possets. Peeled rhizomes can be preserved in syrup, crystallised as a sweetmeat or used in chocolates and biscuits. In Japan, slices of ginger are eaten between dishes to clear the palate. Medicinally, ginger is used to treat flatulence and colic.

The composition of raw ginger is approximately 81% water, 2% protein, 1% fat, 12% carbohydrate, 3% fibre and 1 % ash. Once dried, ginger only retains about 10% moisture. Zingerone (C11H14O3), present in the oleoresin, gives ginger its pungency. Ginger stimulates circulation, promotes sweating and prevents nausea; it is also used as an expectorant, antispasmodic, carminative and antiseptic. The dried root can warm and stimulate the lungs, prevent travel sickness and help severe morning sickness in pregnancy.

China is the largest producers of ginger, followed closely by India and Taiwan. Annually, India exports some 5000 tonnes of dried ginger, and Nigeria, Jamaica, Sierra Leone and Mauritius each export 750-1000 tonnes. Australia's commercial production began in Queensland in the 1960s. Ginger is also now produced in Fiji, Tonga and Uganda. The main importers of ginger are the UK (2000 tonnes), South Yemen (1750-2000 tonnes), USA (1750 tonnes) and Arabia (1000 tonnes). Much of the preserved and crystallised ginger is now exported from Hong Kong and Australia.

Turmeric

The rhizome has a pepper-like aroma, and a bitter but warm taste. It is important in the rice-eating areas of India, southern Asia and Indonesia. It is an indispensable ingredient in the preparation of curry powder, which usually contains about 24% turmeric and gives it the musky flavour and yellow colour. Turmeric is used to colour and flavour prepared mustard, and is also used in relishes, pickles, spiced butters for vegetables, fish and egg dishes and with poultry, rice and pork. In parts of Asia, turmeric water is applied cosmetically for a golden glow to the complexion. Turmeric contains 13% water, 6% protein, 5% fat, 69% carbohydrate, 4% ash and 3% fibre. Distillation yields 1.3-5.5% of volatile oil, which is aromatic, orange-red in colour and slightly fluorescent. Its main constituent is turmerones (C15H22O), and the colour is curcumin (C21H20O6).

Vanilla

Vanilla is an important and popular flavouring and spice. It comes from the fully grown, ripe fruits of an orchid, usually referred to as vanilla 'beans' or 'pods'. An extract from these pods is used to flavour ice-cream, chocolate, beverages, cakes, custard, puddings and other confectionery. The fragrance is used in perfume, soaps and other toilet and household preparations. Medicinally, it has been used as a nerve stimulant and an aphrodisiac.

The fragrance and flavour of the vanilla beans is due to vanillin. Vanillin is produced by an enzyme action during curing. Climate, soils, altitude, extent of pollination, degree of ripeness at harvesting and method of curing all cause the vanilla flavour to differ in different parts of the world. Artificial vanilla flavours exist, but have to be identified as such in manufactured products.

Before 1840, vanilla production was limited to tropical America, mainly Mexico, and was dependent upon natural pollination. This made the product very expensive. Once hand pollination was understood, vanilla production was possible in other tropical areas. The production of cheap, synthetic vanillin resulted in a decline in the price of the natural product. Mexico continued to be the largest producer until the end of the 1800s; the Malagasy Republic now produces 60-80% of the world's vanilla. Production has exceeded demand, and this has led to the accumulation of large stocks. Other countries producing substantially smaller quantities are the French Pacific Islands, Indonesia, Mexico, Réunion and the Comoro Islands, with smaller production in the Seychelles and Uganda.

Black pepper

Black pepper is probably the most widely used condiment worldwide. It has a stimulating action on digestive juices and aids digestion. New methods of food preservation have reduced the use of curative pepper, with the exception of the canning of meat.

It is primarily eaten ground into powder, but can be used whole in pickles and other dishes. Pepper contains the alkaloid piperine, and a lesser amount of piperidine. Piperine content indicates whether ground pepper has been adulterated. Its pungency is due to the resin chavicine, and the odour to a volatile oil containing terpenes. Black pepper contains 8-13 % moisture, 22-42% starch, 5-8% piperine and 1-2.5% volatile oil. White pepper contains about 50-64% starch.

Before the Second World War, Indonesia was the main producer of pepper; however, during the Japanese occupation, trade was cut off and gardens were neglected. The result was a serious shortage of pepper in the postwar decade. This stimulated an increased production in Sarawak and, by 1956, it provided 40% of total world exports.

Cinnamon

Cinnamon is cultivated for the spice contained in its dried inner bark. This is light brown in colour, with a delicate, sweet and warm aroma. The bark is used in powdered form, or made into quills infused whole to flavour confectioneries, breads, cakes, apple pies and curries. It is also used as an alternative to chocolate in hot wine drinks or sprinkled on cappuccino coffee. The principal component of the essential oil of cinnamon bark is cinnamic aldehyde, used to flavour confectionery, drugs and liqueurs, and to perfume candles, incense, dentifrices and toiletries. It contains about 60% cinnamic aldehyde and 10% eugenol. Cinnamon leaf oil is distilled from green leaves, and is used in perfumes, flavourings and in the synthesis of vanillin. Sri Lanka produces the best quality and greatest quantity of cinnamon; it exports some 3000 tonnes annually, 50% of which is imported by Mexico. Germany, USA and UK are the next largest importers.

Cloves

In Asia, cloves are used as a table spice and it is an ingredient of curry powder along with chillies, cinnamon, turmeric, dill and other spices. Cloves are also used to fasten betel quid (see cardamom above). Medicinally, cloves are used as a stimulant, antispasmodic and a carminative. Clove cigarettes were first produced in Indonesia in 1916, and contain one third shredded cloves mixed with two-thirds tobacco. In the West, cloves are mixed with spices in powdered form, or used whole in baking and preserving. They season tomato and other sauces, as well as sausages. It is a characteristic spice associated with Christmas mincemeat and hot wine puches. The dried fruits (mother of cloves) are sometimes used as an adulterant and as a spice.

Nutmeg and mace

Historically, this spice's acquisition involved much bravado and piracy. It was one of the first global commodities, and so great in importantance that, under the 1667 Treaty of Breda, Holland traded New Amsterdam (now known as the New York borough of Manhattan), to the English for Pulau Run, one of the nutmeg islands in the Bandas.

The fruit of the tree yields two spices, nutmeg and mace. Nutmeg podwer is used to flavour baked goods, confections, custards, rice puddings, meats, sausages, sauces, vegetables and beverages such as eggnog, punches and possets. Mace is favoured for savoury dishes, such as pickles and ketchups. The official British Pharmacopoeia lists nutmeg's properties as stimulative, carminative, astringent, antispasmodic, preventing vomiting, stimulating appetite, anti-inflammatory and aphrodisiac. In southeast Asia, the pericarp (husk) is made into sweetmeats and jellies. It is thought that that nutmeg is one of the principal ingredients of Coca-Cola, as the company is one of the biggest consumers of nutmeg in the world.

essential oil of nutmeg and a fixed solid called nutmeg butter are both used for ointments, perfumery and condiments. The oils from nutmeg and mace, though from the same fruit, have distinctive flavours. Nutmegs contain 9% water, 27% carbohydrate, 7% protein, 33% fixed oils and 5% essential oils. By comparison, mace only has 23% fixed oils, but 10% essential oils. These essential oils can used for rheumatic pain and, like clove oil, can be applied as an emergency treatment to dull toothache. In France, they are given in drops in honey for digestive upsets and for halitosis.

Post-harvest

Cardamom

Cardamom seeds can be bleached to a creamy white colour in the fumes of burning sulphur. After curing and drying, the small stems are removed by winnowing. 'decorticated' cardamom consists of husked dried seeds. The essential oil content is 2-10%, found in large cells just under the skin of the seed coat. The oil is used in perfumery, for flavouring liqueurs and bitters, in the preparation of tincture and as a stimulant.

Ginger

The dried ginger rhizome can be used unscraped (coated, with its cork layer intact), or partly scraped or scraped and peeled (uncoated, with all of its cork, epidermis and hypodermis removed). The best Jamaican ginger is dried in the sun for five to six days. In some countries, the rhizomes are plunged into boiling water to stop growth, after which they are sun-dried with or without peeling. Scraped Jamaican ginger is a very light buff colour with a fine aroma; incompletely scraped African ginger is darker in colour but lacks aroma; Indian ginger varies in colour, often still has some epidermis attached and is strongly aromatic. Zingerone gives the spice its pungency. Ginger contains about 2% essential oil, the prinicpal component of which is zingiberene. The oil is distilled from rhizomes for use in the food and perfume industries. Preserved ginger, which is sometimes stored in brine while awaiting processing, is produced by boiling the fleshy parts of the peeled rhizome and storing them in a sugar syrup; crystallised ginger is produced in the same way, but dried and dusted with sugar.

Ginger beer is made from fermenting a mixture of ginger, water, sugar, cream of tartar, yeast and water. Lemon peel and juice or citric acid can also be added. Ginger beer is bottled before fermentation is complete, and it is carbonated and mildly alcoholic. Ginger wine is also alcoholic. Ginger ale is a soft drink made by combining carbonated water with essence of ginger or capsicum extract, colouring and sugar or glucose. Ginger ale is often used as a mixer drink with whisky and other spirits. The non-alcoholic version of ginger beer is not as sweet as ginger ale, but retains a stronger ginger flavour.

Turmeric

After harvesting, the tops of tumeric rhizomes are cut off and cleaned. The primary tubers are separated from the 'fingers' (side rhizomes). For local use, the rhizomes may be used fresh but they are usually boiled in water. A little cow dung is added to this mixture, and it is dried in the sun for seven to eight days before the rhizomes are polished by hand or by rotation in a mounted drum. Dried rhizomes vary from 2.5 to 7.5 cm in length. The green or raw turmeric yields 17-25% of dried product, which is graded into bulbs (rounds) and splits (fingers). The spice is usually sold in ground (powdered) form. Distillation yields 1.3-5.5% essential oil, the main components being turmerone and arturmerone. The colour is a result of curcumin.

Paper tinged with a tincture of turmeric can be used as a test of alkalinity as, when an alkali is added, it turns from yellow to reddish brown, becoming violet when dry. This is not to be confused with litmus paper which also measures alkalinity, but is made from lichens.

Vanilla

Vanilla extract is obtained by macerating the cured beans in alcohol. The curing process should begin within a week of harvesting. This consists of alternate sweating and drying for six months to remove 70-80% of the moisture, and develop the typical vanilla aroma. Good quality beans should be very dark in colour, long, flexible, oily, smooth, and strongly aromatic. In some countries, the pods are 'killed' by keeping them in an oven at 60ºC for 30 seconds or so to speed up the curing process. Cured beans are graded, smoothed, straightened, tied in bundles of 50-90 bean pods and exported in sealed boxes. A yield is considered good at some 800 kg of cured beans per hectare during a crop life of seven years. The beans are prone to mildew, but root rot and insect pests are not a serious problem. The strength of the product depends on whether it is an 'extract' or an 'essence'. The dried pods can be opened and directly infused in milk for puddings and custards.

In 1858, Gobley first isolated vanillin from vanilla. In 1874, Tiemann and Haarman produced an artifical form from coniferin, a glucoside found in the sapwood of certain conifers. Synthetic vanillin is cheaper to produce that from natural beans, but the flavour from the plant is far superior.

Black pepper

Black pepper is derived from the whole dried fruit, and white pepper from the fruit after it has been retted in water and had its mesocarp removed. Black pepper is dried in the sun, and the stalks are removed by winnowing. The pepper is improved if scalded for a short time before drying. A well-cultivated vine can yield 1-1.50 kg green pepper in its third year, and 3-9 kg annually in subsequent years, with a decrease after 20 years. Pepper is a labour-intensive crop, and 45 kg of freshly picked green pepper produces some 12 kg of white or 15 kg of black pepper.

Cinnamon

After fermenting for a full day in covered heaps, the skin, cork and green cortex of cinnamon stems are removed by scraping. While the scraped bark is being dried, stems contract. These can be made into pipes or quills, packed inside one another to form a compound quill 1 m long. After further drying in the shade, daily hand-rolling makes them firmer and more compact. Dried quills are pale brown in colour, and are graded according to bark thickness, appearance, colour and aroma. The thinner the bark, the better the grade: commercial bark should be no more than 0.5 mm thick. Broken quills are exported as 'quillings', while the inner bark, twigs and twisted shoots (featherings) are used mainly for grinding or the distillation of cinnamon oil. 'Chip' are also used for distillation into cinnamon bark oil. These are the trimmings from cut shoots before peeling, shavings of outer and inner bark which cannot be separated and pieces of thick outer bark.

Cloves

Clove oil is used in the manufacture of perfume, being grown specifically for this purpose in the tropics. The dried fruit of cloves contain very little oil. Oil of cloves is extracted from the dried stems, and contains 5-6.5% oil with 80-95% eugenol. The dried leaves contain about 4% oil with 75-88% eugenol. Eugenol is used to prepare microscope slides for viewing, and as a local anaesthetic for toothache. Vanillin is made from eugenol and is used in germicidal perfumes, mouthwashes or as a sweetener and intensifier.

Clove wood is used in the manufacture of newsprint paper, fibreboard and rayon. The bark of some species can be used for tanning.

Nutmeg

When the seed is removed from the pericarp, mace is taken off and flattened by hand or between boards. The colour changes from red to yellow during curing, but it is the brightness of the colour that is important. Nutmegs are then dried in wooden trays under cover until they rattle; they are then shelled by tapping on the end with a wooden mallet. Nutmegs are graded according to size, and vary from 100-250 nuts per kg. When dried, nutmegs look like greyish-brown ovals with furrowed surfaces: larger nuts can measure 30 mm long and up to 18 mm in diameter, and attract higher prices. One hundred nutmegs produce 0.85 kg of mace. The nuts are sometimes treated with lime to prevent insect attack when exported, however this also inhibits germination. Nutmeg and mace contain 7-14% 'oil of nutmeg'. This is produced by distillation, and is used externally in medicine and perfumery. The oil's principal components are pinene, camphene and dipentene. Nutmeg yields about 24-30% fixed oil called nutmeg butter or oil of mace. These are made from broken seeds and mace not good enough for the spice trade pressed between hot plates. The principal component is trimyristin. These oils are used as condiments, carminatives and to scent soaps and perfumes. An ointment of nutmeg butter has been used in treatment of rheumatism, and as a counter-irritant.


From: Seeds of trade (http://www.nhm.ac.uk/seeds)

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