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). Because coffee beans vary, color is not an especially accurate way of judging a roast. Roast degree is one of the most misunderstood things in coffee. Instead of ordering looking at roast as a color, coffee drinkers should think about flavor profile, such as full bodied, rich, nutty, crisp or bright, and ask for that instead - you have a much better chance of getting what you're looking for.
Before roasting, green coffee beans are soft, with a fresh “grassy” smell and little or no taste. Good roasters use different roasts for different beans for many reasons, and a lot goes on in the transformation from light to medium to dark. The coffee roasting process transforms these raw beans into the distinctively aromatic, flavorful, crunchy beans that we recognize as coffee.
Other factors of course enter into the complex equation that determines your coffee’s taste; coffee bean origin, age of coffee, processing method, and so on, but having a basic understanding of roast will give you a rough guide of what type of flavor to expect.
In the next three posts we will cover the various roast types beginning with:
Light Roast Coffees
Light roasts are light brown, tan, in color, with a light body and no oil on the surface because the beans have not been roasted long enough for the oils to break through to the surface.
Light roasted beans generally reach an internal temperature of 180°C – 205°C (356°F – 401°F). At or around 205°C, the beans pop or crack and expand in size. This is known as the “first crack” (for the “second crack,” see below). So a light roast generally means a coffee that has not been roasted beyond the first crack.
Light roasts also retain most of the caffeine from the coffee bean. Light roasts have the highest acidity and are the brightest of the three roast levels. The characteristics of different origins are most pronounced in light roasts, as are the qualities of the individual coffee.
These days there’s a trend in single-origin coffees, made with beans from a single farm, or even a single lot from that farm. This is where a lighter roast makes sense, because it highlights the unique qualities of the coffee, and you’ll be able to taste floral notes, strong berry flavors, clove or chocolate. Often coffees that are light roasted don’t taste balanced (meaning equal amounts of body, acidity and fruitiness) because light roasted coffee can taste extreme. "Too much citrus." "Too much floral." Lighter roasts may require some adventurous coffee drinking (and skilled roasting), but they’re definitely worth a try.
Next week we will cover Medium Roast Coffees.