Kinds of Coffee
There are two main types of coffee that are produced in various parts of the world: Arabica and Robusta.
Arabica Beans - Named for the Arabs who first grew them, Arabica beans are characterized by rich, complex flavors. The individual coffees will vary in flavor and nuance depending on where they are grown. Coffee connoisseurs prize Arabica Beans. Coffee fanatics will be able to distinguish the different regions where the Arabica beans came from, much in the same way that wine experts can recognize where certain grapes were grown. The finest coffee beans tend to come from mountainous tropical areas near the equator.
Robusta Beans - Higher in caffeine than their Arabica cousins, Robusta beans, despite their impressive sounding name, have less complex flavors. Most of your mass produced supermarket blends will be made from Robusta beans, sometimes with a little Arabica thrown in to boost the quality.
How Coffee is Processed
What eventually becomes what we know as a coffee bean starts out life as the seed of a fruit that resembles a cherry. Before they can get anywhere near your coffee pot, the beans must be extracted from the coffee fruit. Depending on the area where it is grown, coffee can be either wet or dry processed.
Wet Processing -- In general, wet processing will result in coffee with higher acidity levels and more consistent results, while the dry method often results in more complex flavor and body in a more volatile product. After processing, the beans are milled to remove any leftover parchment or thin skin that naturally covers the beans. Wet Processing is usually used in areas with an abundance of fresh water. A machine strips the coffee cherries of their skin and outer pulp, leaving the beans still encased in a sticky inner pulp. The pulp encased beans are then wrapped in parchment and soaked for 1 to 3 days in large fermentation tanks. After the soaking, the pulp is washed away before the beans are dried, either naturally in the sun or by mechanical means.
Dry Processing -- Coffee cherries are allowed to dry in the sun in the dry (or natural) processing method.
Once processed, coffee beans are a pale green color. It is not until they are roasted that their full potential and flavor can be realized. Depending on the beans and their intended purpose, coffee may be roasted from 10 to 15 minutes. A roasting professional will monitor the temperature of the beans throughout the process, carefully adjusting and fine tuning to achieve precise results. The roasting machine keeps the beans moving (much in the way at movie theater popcorn machine keeps kernels moving) to insure that the beans evenly roast, not burn. During the coffee roasting process the beans will toast, pop open, and release their natural oils, giving the freshly roasted beans have a shiny appearance. Generally speaking, the darker the roast, the less caffeine, as dark roasting destroys some of the caffeine.
More important for coffee connoisseurs is the amount of time between roasting and drinking -- the shorter the time between roasting and drinking, the better. According to Tom Medin, owner of Local Tastes of the City Tours in San Francisco, no self respecting coffee aficionado would even go into a coffee shop that doesn't have its own roaster on premises. Luckily in San Francisco, that doesn't present a problem. Java junkies who live in less coffee centric areas might want to check out the i-Roast home roasting system. This nifty gadget lets you roast your own coffee, in small batches at home, to your precise taste. Two preset roasting options get you started, from their you can easily modify the process to create your own personal ultimate cup of coffee.