There are many species of coffee plants. The main variety is Coffea arabica, which makes up about 75 percent of the world’s coffee trade. The slightly less refined and cheaper Coffea canephora (robusta) takes up about 20 percent, which a variety of other coffee plants, including Coffea congensis, Coffea bonnieri, Coffea gallienii and Coffea mogeneti. The two main types, arabica and rustica, are then subcategorized by location. The beans are then further divided according to roast.


Arabica Coffee Plant

Coffee from the traditional Coffea arabica plant is generally regarded as superior to all others. The plant is, however, more difficult to cultivate as it is more vulnerable to disease and requires specific conditions. Coffea arabica is primarily produced in Central America, South America and Central Africa because these areas provide the altitude and warm temperatures the plant requires to thrive. The high cost of harvesting and transporting the beans is deemed worthwhile due to the sweet aromatic coffee produced.

Robusta Coffee Plant

Second in line for most popular coffee plant, Coffea canephora, is far easier to cultivate and therefore a cheaper choice. These beans not only have double the caffeine but are more bitter than their Arabica counterparts. It is grown at low altitudes in humid climates, as in Brazil and West Africa. There is one very expensive and sought-after variety of robusta coffee from Indonesia called kopi luwak.

Subvariety Classification

Both robusta and arabica obviously have subvarieties, which are primarily distinguished by where they’re grown. This is because the same plant in a different location can produce very different-tasting coffee due to factors from the nutrients in the soil to the way the beans are processed. The aforementioned java, for instance, comes from Indonesia while mocha comes from Yemen.

Coffee Blends

To create more complex cups of coffee, beans from different areas of the world are blended together. A traditional blend utilizing arabica coffee beans is mocha-java, a combination of mocha and java beans. Mocha beans have a rich chocolatey quality, one that inspired the creation of the popular “mocha” coffee drinks, flavored with chocolate. But not all blends are tried and true. Coffeehouses often create unique “house blends” to serve as their signature coffee. Blending is a good way for smaller coffee companies to cut costs. Instead of using pure arabica beans, Robusta is incorporated as filler. Inexpensive coffee brands, such as Maxwell House and Folger’s, frequently employ this tactic.

Roasts

Roasting the beans is meant to bring out the flavor and aroma of the coffee beans. The roasting method can greatly influence the flavor of the product. The standard American roast, for instance, produces the average, middle-of-the-road cup of coffee created by common American brands. Brazilian roast has a fuller body. Even darker is French roast, which has a deep, rich flavor. The familiar espresso is the darkest roast, with beans roasted to the brink of burning.