Coffee is a brewed drink prepared from roasted coffee beans. The coffee beans are in fact the seeds of the Coffea plant berries and they are also referred to as coffee. Green (unroasted) coffee is one of the most traded agricultural commodities in the world. The most used species are Coffea arabica, and Coffea canephora, (robusta).
Coffee is one of the most popular drinks in the world, and it can be brewed in various ways. Beans are ground and then brewed to make coffee. Depending on the brewing method the taste and flavor profile can be very different. The most popular brewing methods are:
The coffee beverage is slightly acidic, with a pH between 5.0 and 5.1. It has a stimulating effect because of its caffeine content and touted as a potent antioxidant. Coffee is mildly addictive because of the stimulating effect of its component, caffeine, and can cause withdrawal symptoms.
There are numerous documented health benefits associated with coffee consumption, some related to the caffeine, some related to the antioxidants in the beans.
The abuse, however, will cause more problems than benefits.
The word coffee is also used for the coffee plant or the color medium to dark brown.
The most used beans for coffee brewing are Coffea Arabica, (coffee Arabica) and Coffea Canephora, (coffee Robusta).
Out of the two, coffee Arabica has a milder taste, with desired aromatic notes, and it is the choice of most coffee drinkers. Some popular varieties of Arabica are Bourbon, Typica, Sumatra, Caturra, Sulawesi, Mundo Novo, Tico, San Ramon, Jamaican Blue Mountain, Santos, Java, Geisha, (Gesha), Yirgacheffe, Sidamo, Harar, Colombian. Arabica coffees are roasted to various degrees from very light to extremely dark. A lighter roast will preserve the terroir aspect of the beans, a desired feature, looked for by coffee aficionados. An interesting variety is Charrier coffee, (Coffea charrieriana), which contains almost no caffeine. Charrier coffee is getting a lot of interest as an alternative to decaffeinated coffee.
The Robusta coffee is a variety of Coffea Canephora, and it is the most used variety. The Robusta coffee is prised for its high caffeine content, and its ability to yield more crema when pulled into espresso shots. Although there are some great tasting Robusta cultivars, most of them have a rubbery, bitter taste when brewed. This makes Robusta unappealing for coffee lovers, and it is mostly used in blends, to improve caffeine content, or to increase the crema yield. Robusta is, generally, cheaper than Arabica, so it is a popular addition to inexpensive blends.
Besides the Arabica and Canephora, there are two other coffee species with a commercial interest: Liberica coffee and Excelsa.