The Coffee ("Caffè" in Italian)

In botanical terms, coffee makes up the Coffea genus of the Rubiaceae family.
Approximately 60 species of Coffea are identified, but the most important include:

Coffea arabica or Arabica coffee, accounting for 85-90% of world production, Coffea canephora or Robusta coffee, contributing 10-15% to world production, Coffea liberica or Liberica coffee and Coffea dewevrei or Excelsa coffee, which together only account for less than 1% of total production.

The tropical regions of Asia, Africa and America, extending from the Tropic of Cancer to the north and the Tropic of Capricorn to the south, provide the perfect natural habitat for Coffea plants.
Commercial cultivation demands very specific conditions, however, and these vary according to the variety grown.
Ideal average temperatures range between 15-24° C for Arabica coffee and 24-30° C for Robusta.
Arabica thrives best in hilly higher elevations of between 700 and 1700 meters, whereas Robusta is typically found between 200 and 800 meters.
All coffee varieties require abundant rainfall of 1500 to 3000 mm annually depending on soil conditions.
Thus, droughts as well as frost and wind are key factors affecting coffee stocks and prices.

The Plant Coffee plants, with deep green leaves resembling laurel, may grow as shrubs or trees to a height of 10-15 meters at maturity but are kept at three meters on plantations for harvesting purposes. Living as long as 60 years, the shrubs remain productive for 15-20 years.

The Flower Clusters of small white flowers form on the secondary branches of the Coffea shrub in continuous cycles throughout the year, due to the uniformity of the tropical climate. Also known for their pungently rich perfume, Coffea flowers are self-pollinating and wither within a few days to produce their fruit.

The Fruit The fruit of the Coffea is a drupe of one and a half centimeters in diameter that is similar to a cherry, both in its soft, sweet pulp and its bright red color when fully ripe. The fruits are left unpicked until they reach the ideal stage of ripeness, usually after about seven months. Each coffee fruit contains two semi-oval, furrowed seeds or beans, covered with a silver-colored membrane and enclosed in a second, tougher skin called parchment. Arabica and Robusta beans are clearly distinguishable in shape: Arabica being flatter and oblong with a crooked furrow, compared to the convex and rounder Robusta with its straight center furrow.

The Harvest Given their continuous blossoming, Coffea plants may carry green fruits, fully ripe red cherries and overripe ones, all at the same time. To avoid mixing the fruit and potentially contaminating a crop with either green or overripe beans, handpicking is the best method of coffee harvesting. This also allows for green fruit to stay on the tree for the next round of harvesting, and overripe fruit to be naturally discarded by falling to the ground. A quicker, but far less accurate and common method of harvesting is "stripping", whereby branches are stripped of all their fruit either by hand or the use of special machines.

Processing Two ancient methods are still used today to extract coffee beans from their cherries after harvest: the dry process and the wet process. The dry process is necessary for fruit that has been harvested by stripping. Once separated from other matter such as leaves and bits of wood or pebbles, the coffee cherries are spread out in the fresh air on threshing floors to sun dry for a few days. Then, they are put through a hulling machine that frees the beans by crushing the hulls and parchment. The dry method produces "natural" green coffees, also called "unwashed" green coffees. The longer and more complex wet process is mostly used for coffee cherries that are handpicked, and thus more uniform in size. Once gathered, the fruit is put into pulping machines that free the seeds in their parchment from the hulls. The beans are then fermented or "washed" in large water tanks for several days to remove any remaining decomposed pulp formed during this phase. This operation also triggers off a series of chemical reactions in many Arabica varieties that enhance the coffee's aromatic and flavor qualities. The washed beans are then sun dried, freed from their parchment with the use of centrifugal force, then polished and electronically sorted to weed out defective beans and finally, graded for size, form and color ready for selection and shipment.

Selection No other agricultural product is put through such a continual series of quality control tests, as is coffee. Beyond the detection and elimination of defective beans, these controls ultimately serve as a basis for the final selection of green coffees that meet the quality and taste specifications required for proper blending. Expert coffee buyers perform these decisive tests on samples prior to purchase, thus guaranteeing that only the highest quality reaches your cup.

Shipment Green beans are shipped unroasted in 60 kg. (132 pounds) jute bags from producing countries, since the green bean preserves its unique characteristics longer than the roasted bean.

Blending No one coffee and no one crop of the same coffee unites all the characteristics necessary to create the balance in taste, richness of aromas and fullness of body that determines a truly fine espresso. Such balance can only be achieved by blending superior beans of different origins and characteristics, and the greatest homogeneity in taste and aroma is reached if blending is performed before roasting.

Roasting The most critical phase in coffee processing, roasting gives coffee its unique aroma, taste and color. Seventy percent of the final characteristics that make coffee one of the most enjoyable beverages in the world, and Nespresso the most perfect of espressos, are realized during roasting. As the temperature rises in the huge rotating cylinders of the roasting machines, the beans lose 20% of their weight through moisture evaporation. At the same time, the beans expand, increasing by 60% in volume due to physio-chemical reactions that activate substances inside the cells which are responsible for coffee's flavor and its over 900 volatile aromas. Temperature is precisely controlled to never exceed 230° C (446° F) and to never vary from batch to batch of the same blend. The longer the roast and the higher the final temperature, the stronger and more intensive is the final flavor. Roasting times of Nespresso varieties vary between 6 and 11 minutes, producing the exquisitely subtle differences in each blend's flavor and bouquet.

Sources:
Alain Stella, "Le Livre du CafÈ", Flammarion: Paris, 1996.
Philippe Jobin, "Les CafÈs Produits dans le Monde", P. Jobin & Cie: Le Havre, 1982.
"Coffee", Documentation Centre, Nestec Ltd: Vevey, 1989.
Sergio Michel, "The Art and Science of Espresso", CBC, Trieste, Cod. Art. 7128.
ICO Fact Sheets, International Coffee Organization, London.

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