A raw, un-roasted coffee bean isn’t much to look at.
It’s faded, greenish, small and kind of shriveled, with a relatively smooth half-moon surface on one side, and a small crack winding through the flat exterior on the other. But to coffee roasters, the do-it-all artisans of the coffee trade, the ones who turn raw beans into the dark, stimulating brew that steams in our cups and mugs every morning, these green coffees are reservoirs of information.
Artisan roasters can glance at a tray of green coffee beans and pinpoint the processing method; “washed” in water or “natural”, dried in the sun. These roasters can oftentimes pinpoint the origin of the coffee, be it central or south america, africa or indonesia. Contrary to popular belief, the true purpose of roasting is not so much to define the coffee flavor, but to coax out the best characteristics of a specific coffee. A single coffee offers several inherent flavors and aromas, but the roast level will determine which and how many of those flavors are exposed.
There’s no one correct way to roast a specific coffee. It’s up to the roaster to interpret a coffee’s strengths and weaknesses and draw out the best qualities for the consumer. Once a roaster settles on a successful roast profile, he sticks to that roast profile religiously, as consistency is the key to a good coffee. the roasting process removes much of the moisture from the bean while caramelizing the sugars inside, contributing to a coffee’s color, flavor and body.
During the roasting process, the coffee emits two loud pops, known, in the roasting trade, as first crack and second crack. at first crack, the beans are relatively uneven in color, but as the interior temperature of the beans continues to rise, they experience a more uniform browning. This is the moment of truth for coffee roasters; a roast that’s stopped midway between first and second crack is generally considered a light roast, a coffee that’s roasted just barely beyond the second crack is a medium roast, and a coffee that’s roasted well beyond the second crack is a dark roast.
Watching an artisan work the roasting machine illuminates the importance of the human element in the process. Periodically pulling small samples to check the color and aroma, the colors of the roasting coffee can reveal a lot and are as important to the artisan roaster as the colors of bread to a baker.