Different types of coffee roasts are achieved by roasting coffee beans for varied lengths of time. Since this occurs along a spectrum there is a very broad range of roasts starting with extremely light to very dark. How coffee beans are classified within the two ends of the scale is often determined by the individual coffee roaster.
More recently an objective measure of coffee roast called the Agtron gourmet scale has been implemented by the SCAA. The process involves measuring the near-infrared wavelengths of a roasted sample of whole coffee beans and ground coffee beans. Based on the thermal absorbency of the coffee it is classified along a scale starting at #95 (light) to #25 (dark). The equipment to perform these measurements is extremely expensive and most roasters rely instead on color tiles to classify their coffee beans.
There is a general consensus of a few basic coffee roast categories (ordered from light to dark):
- Light Cinnamon
- New England
- Viennese or Full City
- Italian or Dark Roast
For more information about how these categories fit into the major Light, Medium and Dark roasts, please visit our information pages: