Coffee tastes great and may be considered an elixir for some, but there is quite the process that coffee beans go through before it reaches the mugs of the consumer. From the post on coffee beans, we know that they are harvested from the coffee plant and shipped around the world “green,” yet magically are roasted and ready to go by the time we order a cup of coffee in a café or buy coffee grounds in the store. You can eat the green coffee beans; they just wouldn’t taste anything like coffee. Before roasting, coffee beans are green or grey in color and are soft and spongy, with a grassy smell. The roasting process—wherein the beans are cooked with a dry heat and constant agitation for even heating—brings about a chemical change in the beans which brings out the flavors and aromas that we associate with coffee.
At this time there is no industry standard for roast names or descriptions but there are four generally agreed upon main categories: light roast, medium roast, medium-dark roast, and dark roast.
Light roast coffee beans are generally a light brown color and have no oil on the surface of the bean. Preferred for milder coffees, light roast beans have a pronounced acidity and a toasted, grainy taste. Beans in this roast category get their name because they generally not roasted beyond what is called the first crack. There is a temperature threshold (around 300-350°) in the roasting process where coffee beans pop and expand, usually referred to as “cracking.” There is a first crack and a second crack. Light roast coffee beans are not roasted beyond the first crack.
Coffee made from lightly roasted beans also retain the most caffeine. If you are in desperate need of a wake-up in the morning, look for light roast coffee. Common light roast names include: Light City Roast, Half City Roast, Cinnamon Roast, and New England Roast.
Medium roast beans are, not surprisingly, a medium brown color. They also have no oil on the surface of the bean but lack the grainy taste typical of light roasts. Instead, medium roasts tend to have more of a balance between flavor, acidity, and aroma. Medium roasts have less caffeine than light roasts but retain more caffeine than dark roasts. Contrary to popular belief, the darker the roast the less caffeine it contains. Medium roast coffee beans are roasted through the end of the first crack and just before the beginning of the second crack.
Studies have found that medium roasts are not only the most popular in the mass commercial market but are also generally preferred by those in the United States (hence, the American Roast name). Common medium roast names include: City Roast, Breakfast Roast, American Roast, and Regular Roast.
Following logic, medium-dark roasts contain beans with a rich, chocolate color. They also have some oil on the surface of the bean as the internal temperatures at this point are enough to bring that to the surface. Medium-dark roasts may have a bitter aftertaste, and some might find the coffee to be a bit spicy as the flavors and aromas of the roasting process are becoming more prominent.
Common medium-dark roast names include: Full City Roast, Vienna Roast, and After Dinner Roast.
Dark roast coffee beans are a very dark brown, almost black color and shiny, as the oils in the bean are fully on the surface. This oil can usually be seen in your coffee cup when drinking a cup of dark roast coffee. As mentioned above, dark roasts have the least amount of caffeine because these beans have been heated the longest. Although low in acidity, dark roasts tend to taste bitter, smoky, and can have a burnt quality generally characterized by flavors of charcoal or tar. Because coffee beans are heated the longest to make dark roasts, low quality beans are often used as the roasted flavor completely overtakes the original flavor of the beans.
If you are a fan of dark roasts, you may want to pay attention the next time you purchase them in store as the names of dark roasts in particular, appear to be used interchangeably. Common dark roast names include: Espresso Roast, French Roast, Italian Roast, Continental Roast, and New Orleans Roast.
Blends are just what you’d expect them to be—combinations of the different roasts to make other, unique flavor profiles not achievable with just one roast type. Typically, blends are created using two or more roast types.