What do you need to know about coffee roasting?

When it comes to the art of coffee roasting, the difference between great tasting specialty coffee and mediocre commercial coffee is decided by the artist. In the immortal words of one of my favorite vendors of specialty coffee, some roasters don’t know beans about beans. Even the best Arabica beans can be ruined by improper roasting. This is where you will have the advantage, by knowing the difference in roasts.

For many years, and even today in the eyes of most coffee experts, there are only three degrees of coffee roasting. These are light, medium, and dark. In the last decade or two, coffee roasting has been redefined with a number of “degrees of roasts” but these are all just extensions of the three basic types.

The Three Basic Roasts

What exactly is coffee roasting? It is the process of taking green coffee beans, and bringing out the flavors which are locked in the center of the bean. It is done by a machine which sends hot air through a spinning drum which is continuously tossing the beans. The longer the process, the darker the beans get roasted.

Light Roast

This is where the beans are roasted for only about eight to nine minutes. The beans are a light brown color, resembling cinnamon bark. This roast is popular with many roasters because it is fast, and prevents bean shrinkage. On the negative side, light roast doesn’t allow the beans to develop a full body and taste. You will often hear names like Institutional roast, New England roast, or Half City roast in describing this degree of roasting.

Medium Roast

Also known as regular roast, American roast, or British roast, this process turns the beans a medium, glossy brown. The body is slightly better then light roast, but still has a high acidity (the dry tartness the coffee leaves, somewhat like a dry wine). It is at this point and beyond that you may begin to see droplets of oil begin emerge on the surface of the bean. Medium coffee roasting is the most widely available type.

Dark Roast

Beans are roasted for approximately 15-18 minutes, at which point they will turn a rich dark brown. The beans will become very shiny, as if polished, and you can see the oil rising to the surface.

Dark roasted beans will make a coffee that is usually very smooth, full bodied, and has a richness to its flavor. You may also hear terms such as double roast, continental, or high roast. When done properly, dark coffee roasting makes for an excellent espresso.

What do you need to know about coffee roasting?

Espresso Roast

In Recent years, popularity for a very dark roast bean has started to become prominent, particularly in America, where espresso related drinks seem to indicate an air of sophistication. The mistake here is that espresso is actually a method of brewing coffee, and not a degree of roasting. Those beans referred to as “espresso roast” are dark almost to the point of being black, and there are excessive amounts of oil. At this point the true flavor of the coffee is actually lost, and all you can taste is the roast itself. It is this coffee lovers opinion that beans should never be roasted this dark.


While there is really no universal standards on coffee roasting, the consensus is that the terms light, medium, and dark cover the general spectrum of roasting. But, it would be hard to find much agreement as to how dark to roast which coffees. For instance, another term used for espresso roast is French roast, but you will seldom find many Europeans drinking coffee made from beans roasted that dark. You must consider that the original purpose for the very dark roasts was to disguise the flaws in coffee beans. My suggestion is to try various roasts of different specialty coffees and decide for yourself. You will find the right roast of the coffee that suits your taste.