Looking down at the dark-brown-almost-black liquid in your coffee cup (or light tan, if you’re like me and you need cream and sugar) most of us don’t wonder how our coffee ends up in convenient vacuum-sealed bags in the grocery store. But once you understand the entire process that the humble coffee bean goes through, it’s hard NOT to be impressed that somebody actually came up with the drink that’s so popular today.
Arabica vs. Robusta
First, you should know that there are two main varieties of coffee beans: Arabica and Robusta. If you’ve ever seen the word “Arabica” on your canister of coffee, here’s where it comes from. Arabica coffee has a mild and aromatic taste and it accounts for about 70 percent of the world’s coffee.
The Robusta bean is smaller and rounder than an Arabica bean, but it’s also heartier and can withstand higher temperatures and lower altitudes. Robusta beans also have a bitter taste and contain 50% more caffeine than Arabica, making them popular in espresso blends.
Coffee doesn’t actually start as the beans we’re familiar with – it’s actually a dark red cherry with yellow pulp. The coffee beans are actually inside the cherry. When the coffee cherries are ripe, they are either shaken from the tree or picked by hand. Each coffee tree yields about one pound of roasted coffee.
After the cherries are harvested, the coffee beans are processed to separate the bean from the pulp and remove the skin surrounding the beans. There are two popular methods for removing beans from coffee cherries: the wet method or the dry method. In the dry method, cherries are spread in the sun and raked and turned for seven to ten days, until some of their inner moisture content is lost. Once this occurs, the outer shell of the cherries turn brown and the beans can be heard rattling inside. In the wet method, the beans are extracted from the cherries by a pulping machine within 24 hours of harvesting. Then the beans are put in tanks where enzymes loosen the beans from their skins for 12 to 48 hours. The beans must then be dried by the sun or mechanical dryers before they can be sorted and shipped.
Roasting the Beans
Next the beans are roasted before they can be turned into grounds. This is where the real science comes in. Roasting must be performed carefully because this stage darkens the beans and develops their flavor and aroma. The degree to which beans are roasted affects the flavor of the coffee they will one day become.
Coffee beans are roasted in large, rotating drums to keep them from burning as they are heated to about 550 degrees Fahrenheit. The beans turn yellow as they begin to roast. After about 7-8 minutes, the beans make an audible popping noise, like popcorn, and double in size. Beans are fully roasted after another 3-5 minutes following the first pop—roasters know that the beans are done because they will pop again. Any longer than this and the beans will be burnt.
Most American mass-marketed coffee is light or medium roasted, which means that it is heated for 7-11 minutes. French or Viennese coffee tends to be darker, roasting for about twelve or thirteen minutes. The darkest coffee is consumed by Italy and is often processed into espresso roasts.
Now you’ve got real coffee beans! Of course, some people prefer to buy grounds, but there are many different methods for grinding beans. Some people even prefer to do this step themselves and buy whole beans instead. And there you have it. This lengthy process is why, if you want good coffee from a shop that buys quality beans, you can expect to pay good money for it.