Coffee Cherry: Coffee beans are actually coffee seeds that make up the pit of a coffee cherry. Coffee cherries are picked when they are ripe and bright red in colour.
Coffee Processing: See Processing Link
Cooling tray: The cooling tray is usually circular and equipped with stirring arms that agitate the just-out-of-the-roaster coffee with air being pulled through the tray (and through the mass of freshly roasted beans) to halt the roast by bringing the temperature of the beans down from over 400F down to room temperature. Without forced cooling, the beans would continue to roast beyond the intended rate.
De-gas: The time needed for a batch of coffee to release carbon dioxide for optimum flavour. More degassing is necessary for optimum espresso than is needed for brewed coffee. This takes place for 48 hours after the roast.
Green Coffee: The coffee seed before it is roasted and after it is processed and dried. This is the form coffee is in when it is purchased by a roasting company.
Roast Profile: The rate, timing, temperature and homogeneity of roast rate at various layers of the bean (external and internal). Roast profiling is critical for allowing the coffee’s own characteristics to be highlighted as well as for blending different coffees to be used as espresso or as brewed coffee.
Tryer: On a drum roaster, the tryer is the tool used to collect a sample of coffee to be observed by the coffee roaster during roasting in order to track the profile and progress of the roast.
Light Roast: No oil, usually cinnamon or a little darker in colour. Lighter body, more flavour of origin and acidity comes through.
Medium Roast: Very little to no oil present. Milk chocolate in colour, has added depth of body at the cost of some acidity and possibly at the cost of some origin characteristics.
Dark Roast: Dark, almost black, with ample amounts of oil present on the surface. Almost, or all origin characteristics are gone, the body is beginning to decrease, the flavour is thin, and usually tastes of the roast, including charcoal, bitter flavours and very low acidity.
First Crack: A roasting term. The coffee bean’s first expansion as vaporized moisture escapes. The coffee been expands to nearly double its volumetric size, and a popping sound almost like popping popcorn can be heard.
Second Crack: The coffee bean’s second expansion as vaporized moisture is released, and the bean structure itself begins to fracture. Many of the flavours of origin are burned off during second crack, while body is increased, and acidity becomes more muted, or possibly lacking entirely. A noise sounding much like rice cereal in milk can be heard as the second crack develops.