Roasting and Cupping
Roasting. The way in which coffee is roasted can have a profound effect its taste. Roast too quickly at too high a temperature, and you'll scorch the exterior of the bean. Roast too slowly at too low a temperature, and you'll sap the bean of its of flavor. Over the years, numerous roasting methods have been developed to address these challenges, all with the same objective: To transfer heat to the coffee bean, initiating a series of chemical reactions that prepare it for consumption. Most roasting methods include the following six phases:
1. Drying Cycle:
This is the first phase of the roasting process, when the temperature of the beans rises to 100 degrees centigrade. Also in this phase, the beans change from a bright green color to a pale yellow.
2. First Crack:
When the beans reach 160 degrees centigrade, complex chemical reactions begin to occur causing a cracking sound.
3. Roast Initiation:
The beans swell to 140 - 160% of their initial size. Elements within the beans begin to caramelize, giving the beans their brown color.
In this phase, the audible cracking ceases, but the reactions continue. The time of this silence will depend on the amount of heat applied by the roaster.
5. Second Crack:
The progressive dehydration of the beans has made them brittle. As a result, more cracking can be heard. It is at this stage that elements in the bean begin to carbonize, producing the burnt characteristics of extremely dark roasts.
6. Stopping the Roast:
Once the optimal amount of roasting time has elapsed, the beans must be cooled quickly. This is usually accomplished by introducing large amounts of cool air or water.
Cupping is a method of systematically evaluating the aroma and taste of coffee beans. It is often used by growers, buyers and roasters to assess the quality of a particular coffee sample. Proper cupping requires the adherence to an exacting set of brewing standards and a formal step-by-step evaluation process. A trained cupper generally looks at six characteristics:
Fragrance - the smell of beans after grinding
Aroma - the smell of ground-up beans after being steeped in water
Taste - the flavor of the coffee
Nose - the vapors released by the coffee in the mouth
Aftertaste - the vapors and flavors that remain after swallowing
Body - the feel of the coffee in the mouth