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Can drinking coffee be good for health? Tina Gomes What is coffee? Coffee is a widely-consumed stimulant beverage prepared from roasted seeds of the coffee plant. Coffee berries are produced by several species of small evergreen bush of the genus Coffea .
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Can drinking coffee be good for health? Tina Gomes
What is coffee? • Coffee is a widely-consumed stimulant beverage prepared from roasted seeds of the coffee plant. • Coffee berries are produced by several species of small evergreen bush of the genus Coffea. • The two most commonly grown species are Coffea robusta and Coffea arabica.
Where did it originate? • Coffee was first consumed in the 9th century, when it was discovered in the highlands of Ethiopia. • It was then introduced to Egypt, from where coffee spread to Europe through thriving trade of many goods including coffee beans. • Coffee reached the Americas during colonial period and became a really popular beverage when import of tea from Britain was temporarily cut off during war of 1812.
Biology of a coffee plant • The Coffea plant belongs to the family Rubiaceae. • It is an evergreen shrub or small tree which can grow up to 5 m tall. • The leaves are dark green and glossy, usually 10–15 cm long and 6.0 cm wide. • It produces clusters of fragrant, white flowers that bloom simultaneously.
The fruit berry is oval, about 1.5 cm long, and green when immature, but ripens to yellow, then crimson, becoming black on drying. • Each berry usually contains two seeds • Berries ripen in seven to nine months.
Cultivation of Coffee • Coffee is usually propagated by seeds. • The traditional method of planting coffee is to put 20 seeds in each hole at the beginning of the rainy season. • Coffee is often intercropped with food crops, such as corn, beans, or rice, during the first few years of cultivation. • Originally, coffee farming was done in the shade of trees, which caused berries to ripen more slowly making the quality of the coffee superior.
Processing of Coffee • First, coffee berries are picked. Then, they are sorted by ripeness and color, and the flesh of the berry is removed. • The seeds are fermented to remove the slimy layer of mucilage still present on the bean. • When the fermentation is finished, the beans are washed with water to remove the fermentation residue. Finally the seeds are dried, sorted, and labeled as green coffee beans. • The next step in the process is the roasting of the green coffee. • Depending on the color of the roasted beans, they will be labeled as light, medium, or dark.
Effects of Coffee on health • Coffee appears to reduce the risk of Alzheimer's disease, Parkinson's disease, heart disease, diabetes mellitus type 2, and cirrhosis of the liver • However, it increases the risk of acid reflux and associated diseases • The antioxidants in coffee prevent free radicals from causing cell damage. • Some health effects of coffee are due to its caffeine content, for example, coffee contains an unknown chemical agent which stimulates the production of cortisone and adrenaline, two stimulating hormones.
Caffeine • Coffee's negative health effects are mostly due to the caffeine. • Research suggests that drinking caffeinated coffee can cause a temporary increase in the stiffening of arterial walls. • Excess caffeinated coffee consumption may lead to hypomagnesaemia and coronary heart disease. • Caffeine acts as a stimulant. Consumption of excessive coffee can lead to caffeine dependency and withdrawal symptoms
References • http://en.wikipedia.org/wiki/Coffee_and_health • http://en.wikipedia.org/wiki/Coffee • http://images.google.com/images?um=1&hl=en&q=coffee+&btnG=Search+Images • http://www.health.harvard.edu/press_releases/coffee_health_risk.htm