Coffee Roasting Guide: Light to Dark Roast

Light roast? Dark roast? Sure we all know these terms but what does this really mean and what qualities are coffee roasters looking for in deciding the coffee roast?

You may wonder are there beans that are always light roast or dark roast? Well, yes..There are certain beans that have a very unique flavor profile. In order to preserve this flavor profile, these beans are always light roast coffee. You may be familiar with some of these beans, such as Peaberry, Jamacian Blue Mountain and Kona beans. These beans all have unique tastes that the roasters want to preserve, and therefore do not subject the beans to roasting for long. 

So let's talk about roasting coffee. Coffee is roasted in batches. There is a continuum of roasted coffee from light to dark roast, and the time in the roaster will determine the overall taste and acidity level of the final product. It's important to note that a good cup of coffee starts with quality beans, but is really made by the skill level of the head roaster. Even the finest coffee beans can be ruined by the wrong coffee roasting technique.

Green coffee beans are added to the coffee roaster. The heat is turned up and the beans move around constantly. Once the beans reach a certain temperature, they begin to pop. The beans are similar to popcorn. The beans expand in size when when they pop. If the coffee is removed from the heat soon after the first pop, this is light roast coffee. If coffee is allowed to continue to roast, and is removed from the heat after a few minutes from the first pop, this is medium roast coffee. Dark roast coffee is roasted until there is a second pop of the coffee beans. This causes the natural oils from inside the beans to come to the surface of the bean. Dark roast coffee is not only darker in color, it also has a light sheen on the bean from the natural oils on the surface. It's important to note that only a few minutes separates light and dark roast coffee. 

The few minutes of roasting can really change the flavor profile of the beans. Here are a few of the common descriptions for each of the main types of coffee:

Light roast: Acidic, dry, no real roasted flavor, complex, green, grassy

Medium roast: Aromatic, complex, less acidic, slightly sweet

Dark roast: Spicy, heavy body, full bodied, strong aroma, bittersweet, caramel, bold

So what is your favorite roast of coffee? Light roast? Dark Roast? or Medium?