Before coffee beans can be used to make coffee drinks, they must be roasted. It is the roasting process that transforms them into the aromatic and flavorful brown beans that are used by consumers. Roasting usually occurs in revolving heated metal drums at temperatures between 260-310 degrees C (500-600 degrees F). During this intense heating, chemical transformations of the proteins known as pyrolysis, and carmelization and carbonization of the sugars in the beans results in the production of the aromatic organic compounds which make up the flavour and aroma of the coffee. A roasting house's roasting technique can be varied depending on the bean origin, density, and the flavor profile the roastmaster wishes to develop. This artisan approach to coffee roasting is at the heart of Aura Coffee.
Lastly, the roasted beans are run through an adjustable mechanical grinder that allows the selection of particle sizes corresponding to the different brewing techniques. Finer grinds, typically required for espresso, provide a greater surface area of the powdered bean and allow the maximum taste and aroma to be obtained from the infusion process that is only about 20-25 seconds in duration. At the other extreme, the coarsest grind is used for french press because the infusion process is on the order of 3-4 minutes and the grounds must be large enough to be captured by the plunger screen.