Book ID 331

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CD Encarta

Coffee, common name for trees of the genus Coffea

Coffee, common name for trees of the genus Coffea, of the family Rubiaceae, and also for their seeds (beans) and for the beverage brewed from them. Of the 30 or more species of the genus, only three are important: C. arabica, C. canephora (C. robusta), and C. liberica. The shrub or small tree, 4.6 to 6 m high at maturity, bears shiny green, ovate leaves that persist for three to five years and white, fragrant flowers that bloom for only a few days. During the six or seven months after appearance of the flower, the fruit develops, changing from light green to red and, ultimately, when fully ripe and ready for picking, to deep crimson. The mature fruit, which resembles a cherry, grows in clusters attached to the limb by very short stems, and it usually contains two seeds, or beans, surrounded by a sweet pulp.

1. Production

The soil in which Coffee is grown must be rich, moist, and absorbent enough to accept water readily, but sufficiently loose to allow rapid drainage of excess water. The best soil is composed of leaf mold, other organic matter, and disintegrated volcanic rock. Although Coffee trees are damaged easily by frost, they are cultivated in cooler regions. The growing temperatures range from 13 to 26�C. Altitudes of Coffee plantations range from sea level to the tropical frost level, about 1800 m. C. robusta and C. liberica grow best at altitudes below 900 m; C. arabica flourishes at the higher altitudes. The seeds are planted directly in the field or in specially prepared nurseries. In the latter case, young selected plants are transplanted later to the fields. Commercial fertilisers are used extensively to promote the growth of stronger, healthier trees with heavier yields. Both the trees and the fruit are subject to insect infestation and microbial diseases, which may be controlled by spraying and proper agricultural management.

2. Harvesting

The Coffee tree produces its first full crop when it is about 5 years old. Thereafter it produces consistently for 15 or 20 years. Some trees yield 0.9 to 1.3 kg of marketable beans annually, but 0.45 kg is considered an average annual yield. Two methods of harvesting are used. One is based on selective picking; the other involves shaking the tree and stripping the fruit. Beans picked by the first technique are generally processed, if water is available, by the so-called wet method, in which the beans are softened in water, depulped mechanically, fermented in large tanks, washed again, and finally dried in the open or in heated, rotating cylinders. The so-called dry method, used generally for beans harvested by the second technique, entails only drying the beans and removing the outer coverings. In either case the final product, called green Coffee, is sorted by hand or machine to remove defective beans and extraneous material and is then graded according to size.

3. Characteristics

Coffee contains a complex mixture of chemical components of the bean, some of which are not affected by roasting. Other compounds, particularly those related to the aroma, are produced by partial destruction of the green bean during roasting. Chemicals extracted by hot water are classified as non-volatile taste components and volatile aroma components. Important non-volatiles are caffeine, trigonelline, chlorogenic acid, phenolic acids, amino acids, carbohydrates, and minerals. Important volatiles are organic acids, aldehydes, ketones, esters, amines, and mercaptans. The principal physiological effects of Coffee are due to caffeine, an alkaloid that acts as a mild stimulant.

4. History

Exactly where and when Coffee was first cultivated is not known, but some authorities believe that it was grown initially in Arabia near the Red Sea about AD 675. Coffee cultivation was rare until the 15th and 16th centuries, when extensive planting of the tree occurred in the Yemen region of Arabia. The consumption of Coffee increased in Europe during the 17th century, prompting the Dutch to cultivate it in their colonies. In 1714 the French succeeded in bringing a live cutting of a Coffee tree to the island of Martinique in the West Indies. This single plant was the genesis of the great Coffee plantations of Latin America.

Extract ID: 1285

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CD Encarta


Maasai, East African nomadic people speaking the Maasai Sudanic language. The Maasai traditionally herded their cattle freely across the highlands of Kenya. Probably at the height of their power in the mid-19th century, they suffered from the British colonization of Africa and the resultant ecological and political changes. Rinderpest, an infectious febrile disease, apparently accompanied the British, decimating the cattle herds that supplied the Maasai with milk and blood; famine and then smallpox followed.

Extract ID: 542

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CD Encarta

Maasai males are rigidly classed by age

Maasai males are rigidly classed by age into boys, warriors, and elders. Girls often have their marriages negotiated by their fathers before they are born. Both boys and girls undergo circumcision ceremonies. Older women enjoy the same status as male elders. The Maasai, most of whom are nomadic throughout the year, live in kraals, small clusters of cow-dung huts constructed by the women. Today [1993~] the Maasai number approximately 250,000. They remain a pastoral people.

Extract ID: 547

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The weakened Maasai attacked

The weakened Maasai attacked rather than cooperated with the new rulers. In 1904 and 1912-13 the British government relocated the Maasai population to distant southern Kenya and Tanzania, where they now live.

Extract ID: 545