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Coffee

 



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Overview
It's been used as a medicine and an ingredient in wine. It's been linked with revolutionary ideas. First a food, later a beverage, coffee contributed significantly to the economic health of countries that controlled it. The coffeehouses in the Middle East and Europe that sprang up because of it became centers of intellectual ferment, often frowned upon by the authorities. Native to Ethiopia, this crop is now grown around the world and is a major commodity in the world economy. The principal species, Coffea Arabica, thrives at high elevations in a moist, mild climate where there is partial shade. That's why most of the big coffee producers are located in mountainous countries near the equator. The coffee tree is a shrublike plant with glossy, dark-green leaves and small, white, fragrant flowers. The fruit, or cherry, is initially green and gradually ripens to a dark red. Although people used to eat the coffee cherries or chew the coffee leaves, the principal interest now is in the coffee seeds or beans. Removal of the fruit from the beans requires several steps and considerable water because the inner part of the fruit is so sticky. Processors first pulp and wash the cherries, and then allow them to ferment before washing them again. During fermentation, microorganisms act on the sticky inner layer of the cherry to break it down. Finally, the seeds are dried, and a hulling machine crushes the remaining parchment covering so it can be removed. The seeds-now called green coffee beans-can be roasted in several different ways. To prepare coffee, people brew the ground-roasted beans with hot water, a process that extracts flavor and fragrance chemicals. Only those chemicals that are soluble in hot water dissolve to make the coffee. The coffee grounds are left behind. One chemical naturally present in coffee is caffeine, which is a mild stimulant. But many different chemicals are manufactured by the coffee plant, and other chemicals are created in the roasting process. Most coffee flavor comes from roasting-green coffee beans smell and taste completely different from roasted ones. Caffeine can be extracted from the beans to make decaffeinated coffee without altering the flavor much, since caffeine itself has very little flavor.

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