Delve very deep into coffee and coffee roasting and you will undoubtedly be inundated with cryptic roast degree terms and systems. Full city, light, city, French, dark, Italian, American, cinnamon, Spanish, espresso, Viennese, etc. You may ask “Well Alex, how do all these compare to each other?”, a very good question, to wit I would respond “It depends whom you ask”. Yes, unfortunately there is really no set standardization in these terms. The terms do have a generally accepted range of a degree that they refer to, but when you get down to specifics, they lose their reliability. The terms have no set roasted degree, even the order of roast degree the terms refer to are not kept consistant. Some roasters will have an espresso roast lighter than their French roast, some will be the reverse, Viennese seems to float around, cinnamon and light are often switched, etc. This peeves me. So I try to stick with the following system: Light, medium, and dark. There is no question of which terms refer to roasts longer or shorter than the others, and the specifics are not lost. because the three terms can be further broken down into: very light, light-medium, medium-light, medium, medium-dark, dark-medium, dark, and very dark, and described as follows:
Light - Light brown to cinnamon color Low body and light acidity. The beans are dry. This roast is too light and does not allow the coffee to develop to its full potential.
Medium - Light Medium light brown color. The acidity brightens and body increases slightly. The bean is still dry.
Medium - Medium brown color. The acidity continues to increase and the body becomes more potent. The bean is mostly dry.
Medium - Dark Rich brown color. Very small droplets of oil appear on surface. The acidity is slowly diminished and body is most potent. This is the ideal roast for a well blended espresso.
Dark - Deep brownish/black color. The bean has spots of oil or is completely oily. Subtle nuances are diminished. Flavor decreases, while body dominates.
Very Dark - Black surface covered with oil. All subtle nuances are gone, aroma is minor, and body is thin. This roast is characteristic of American espresso.
To be quantitative and scientific about the roast degree, one can use a machine (called an Agtron) to measure the roast degree of the coffee. The machine produces a number representing the roast degree, thus we can really standardize by saying something like Agtron #60-50 is medium-light roast. What a wonderful world that would be.