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The word qahwa originally referred to a type of beverage made with the seeds of a plant causing stimulant effects on humans. Nowadays, qahwa is the Arabic term for the coffee drink.
The world’s top producers of coffee currently are Brazil, Vietnam, Colombia and Indonesia. The list varies from year to year, but usually Mexico, Guatemala, Honduras, Peru, Ethiopia and India are the other largest coffee-producing nations.
Coffee is a beverage made by roasting and grinding the seeds of a tropical plant (Cofeea), member of the Rubiaceae family. Within the genus, there are over 100 species of tropical trees and shrubs but only ten are considered commercially valuable.
These species vary widely depending on different factors: height of the plants, types of leaves, scent of the flowers, size and colour of the seeds, flavour, caffeine content and resistance to climate change.
The most cultivated and known species are: Coffea arabica (simply known as Arabica), Coffea canephora (also knows as Robusta) and Coffea liberica.
Coffee beans are roasted at approximately 200 degrees C. They tumble on a current of hot air for 4-5 minutes until uniformly roasted. During the roasting, the coffee beans undergo several changes:
• weight loss, due to evaporation
• increase in size
• formation of a dark-brown colour, due to cellulose combustion and caramelization of sugars
• appearance of a brown oil (caffeone) on the outside – it defines its specific aroma
• caffeine content reduction, due to heat
Proportionally to higher roasting temperature, the decrease of caffeine content is greater. Roasting increases also the friability of the product, making it easier to grind the beans.
Coffees of various origins are usually blended so as to make different types of blends.
With a mature taste and sense of smell, expert roasters select the best lots and decide the necessary quantities to balance the flavours needed: velvety, creamy, full-bodied, rich, fragrant, strong, delicate, intense.
Roasting is an art and every roaster keeps it like a secret.