![]() ![]() Most countries require that the content be reduced to less than 0.1% on a dry weight basis. Green coffee beans are swollen to contain 30–40% moisture with water and steam at temperatures of 20–100☌ for up to 5 h and decaffeinated in static or rotating drums with a water-saturated solvent, such as dichloromethane ( Patel & Wolfson, 1972), ethyl acetate ( Morrison & Phillips, 1983) or edible fats and oils ( Malizia & Trumbetas, 1984 Pagliaro et al., 1984), at temperatures ranging from 60 to 105☌ for 2–12 h, depending upon the level of residual caffeine permitted. This technique was patented in 1905 by Roselius ( Meyer, 1906 Meyer et al., 1908 Katz, 1987) and is still the most commonly used. The parchment is removed in centrifugal hulling machines, and the beans are cleaned by density, sorted electronically by colour, graded by size through screens and bagged in 60- or 70-kg jute bags. The beans, which are still surrounded by parchment, are then washed and either sun-dried for four to eight days or dried in a hot-air dryer for 24–30 h. Some pulpers remove skin, pulp and mucilage mechanically in a single operation. ![]() Enzymatic fermentation of the mucilage which still adheres to the bean solubilizes the mass so that it can be removed by stirring with water. In the ‘wet’ or ‘washed’ process, freshly picked berries are separated in water channels into ‘floaters’ (overripe and one-bean cherries) and ‘sinkers’ (ripe cherries), which are pulped mechanically floaters are usually dry-processed and consumed locally. Husks (skin and pulp) are removed in centrifugal hulling machines. They are spread in a thin layer on the ground, where they are sun-dried for up to three weeks. In the ‘dry’ or ‘natural’ process, cherries of different degrees of ripeness are strip-picked and handled simultaneously. ![]() robusta, was introduced during the twentieth century in Asia, Africa and, more recently, Brazil ( Viani, 1986).ĭry and wet processes for processing coffee cherries. A rust-resistant species, Coffea canephora, var. Low-altitude coffee cultures in Asia were destroyed during the last part of the nineteenth century by the coffee rust, Hemileia vastatrix. cultivated in European glasshouses, as first described by Linnaeus in 1737( Debry, 1989), were introduced into the Dutch West Indies and to the Portuguese, French and Spanish colonies of Asia and America ( Wellman, 1961). By the end of the sixteenth century, it had crossed the Mediterranean Sea, and in less than a century it had spread throughout Europe and to the British settlements in North America ( Wellman, 1961).ĭuring the seventeenth century, the cultivation of coffee spread to the Malabar coast of India and to Ceylon and, from the beginning of the eighteenth century, seedlings of Coffea arabica L. It is only by the middle of the fifteenth century that coffee as a beverage ( kahwah in Arabic), an infusion of roasted and ground coffee beans that had been cultivated in the Yemen, near the harbour of Mocha, came into general use throughout the Ottoman empire. Coffee cherries ( bun or bon) were then probably only dried and chewed as a stimulant against fatigue. Commercial and political links were at that time becoming quite strong across the Red Sea. The year 575 is often cited as the date of the arrival of coffee on the Arabian peninsula from Ethiopia. Little of coffee’s original mystique has been worn off by centuries of familiarity.’ ( Hattox, 1988). Even in the late twentieth century, however, it has yet to be relegated to the rank of the more pedestrian potions with which we quench our thirst or warm our insides. ![]() Some three centuries have passed since it became the overnight rage among the fashionable and witty in cities throughout Europe. ![]()
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