What is your favorite coffee roast? Light? Medium? Dark?
The degree to which coffee beans are roasted is one of the most important factors that determine the taste of the coffee. Before roasting, green coffee beans are soft, with a fresh smell and little or no taste. The coffee roasting process transforms these green coffee beans into the aromatic, flavorful and crispy beans that we call it coffee.
Here is a guide to coffee roasts from light to dark.
Of course other factors also determine the coffee’s taste. From the coffee varieties (different countries of origin or grown in different environments can taste quite different even when roasted to the same level, especially at light to medium roast levels), the age of the coffee, the preparation method, the grind, and the brewing method also can affect the taste. But the roast level is primarily the factor that provides the taste we can expect. However, roast level preferences are a bit subjective and are subjected to culture traditions. The roast level you like may depend on where you live. In the West Coast of USA people traditionally preferred darker roasts than those on the East Coast. Europeans also prefer dark roasts, lending their names to the so-called French, Italian, and Spanish roasts that dominate the darker end of the roasting spectrum.
The most common way to describe coffee roast levels is by the color of the roasted beans, ranging from light to dark (or extra dark). During the roasting process the bean color becomes darker. Because coffee beans vary, color is not an especially accurate way of judging a roast. But combined with the typical roasting temperature that gives beans a particular shade of brown, color has become a very convenient way to categorize roasting levels.
Though roast names and descriptions are not standardized in the coffee industry (e.g. Starbucks uses its own terminology: Blonde Roast, Medium Roast and Dark Roast; California-based roaster Rogers Family Company has five roasting levels ranging from medium to extra dark), in general, we can categorize the most common coffee roasts from light to dark as follows:
Green coffee beans as they arrive at the dock are kept at 22 °C (72 °F). The beans can be stored for approximately 12–18 months in a climate controlled. Right after, during the drying phase about 165 °C (329 °F), the beans are undergoing a process until their moisture content is evaporated.
Light roasts are colored light brown, with a light body and no oil on the beans surface. Light roasts have a toasted grain taste and pronounced acidity. The origin flavors of the bean are more retained than in darker roasted coffees. Light roasts also retain most of the caffeine from the coffee beans.
Light roasted beans generally reach an internal temperature of 180°C – 205°C (356°F – 401°F). Around 205°C, the beans pop or crack and expand in size. This is known as the first crack. So a light roast generally means a coffee that has not been roasted beyond the first crack. Some common roast names within the light roast category are Light City, Half City, Cinnamon Roast (roasted to just before first crack), and New England Roast (a popular roast in the northeastern United States, roasted to first crack).
Medium roasts coffees are medium brown in color with more body than light roasts. They also have no oil on the beans surface. However, medium roasts lack the grainy taste of the light roasts, exhibiting more balanced flavor, aroma, and acidity. Caffeine is somewhat decreased, but there is more caffeine than in darker roasts.
Medium roasts reach internal temperatures between 210°C (410°F) and 220°C (428°F), between the end of the first crack and just before the beginning of the second crack. Common roast names within the medium roast level include Regular Roast, American Roast (the traditional roast in the eastern United States, roasted to the end of the first crack), City Roast (medium brown, a typical roast throughout the United States), and Breakfast Roast.
Medium-dark roasts have a richer, darker color with some oil beginning to show on the surface of the beans. A medium-dark roast has a heavy body in comparison with the lighter or medium roasts.
The beans are roasted to the beginning or middle of the second crack about 225°C (437°F) or 230°C (446°F). The flavors and aromas of the roasting process become noticeable, and the taste of the coffee may be somewhat spicy. Among the most common names for a medium-dark roast are Full-City Roast (roasted to the beginning of the second crack), After Dinner Roast, and Vienna Roast (roasted to the middle of the second crack, sometimes characterized as a dark roast instead).
Dark roasts coffees are dark brown in color, sometimes almost black. They have a sheen of oil on the surface, which is usually evident in the cup when the dark roast coffee is brewed. The coffee’s origin flavors are eclipsed by the flavors of the roasting process. The coffee will generally have a bitter and smoky or even burnt taste. The amount of caffeine is substantially decreased.
To reach the level of a dark roast, coffee beans are roasted to an internal temperature of 240°C (464°F) about the end of the second crack, or beyond. They are seldom roasted to a temperature exceeding 250°C (482°F), at which point the body of the beans is thin and the taste is characterized by flavors of tar and charcoal. Dark roasts go by many names and sometimes names can even be confusing. Some of the more popular designations for a dark roast include French Roast, Italian Roast, Espresso Roast, Continental Roast, New Orleans Roast, and Spanish Roast. Many dark roasts are used for espresso blends.
In summary, the choice of coffee, including the optimal roast level, is a personal preference. It is all about your favorite taste, flavor, and aroma. You may prefer a lighter roast (with more caffeine) during mornings or afternoons to wake up or increase your activity level, and a darker one later in the day.