ROASTING THE BEANS
Roasting is a critical factor in creating the flavor profile of the coffee bean. The degree that beans are roasted can determine if the coffee will be light or dark, sweet or bitter.

During roasting the raw green coffee bean loses moisture, turns yellow, and then “pops” open, much like popcorn in about 15 minutes. As this happens, the bean nearly doubles in size, and begins to assume the light tan color of lightly roasted coffee. Once this stage is achieved, the heat source is turned down and the coffee rapidly darkens in color. Once the desired degree of roast for a given coffee has been achieved, the process is stopped by using either a brief spray of water followed by air-cooling or by air alone.

Roasted beans generally fall into four main categories:

Lightly roasted coffees tend to have intense aromas, with crisp, lively acidity as the dominant flavor and a relatively light body.

Medium roast beans are full in body while maintaining most of their acidity.

Dark roasts have a roasty bitterness and a more pungent flavor.

Very dark roasts have a distinctive bitter, carbon-taste as their primary flavor.