Roasting Roasting is the alchemical process that transforms the green bean into a delicate brown bean. Coffee beans are exposed to high heat in a chamber that rotates them to ensure balanced exposure to the roasting heat.
Coffee roasting is a simultaneous process of creation and destruction.
Intense heat disrupts the molecular compounds and the woody structure of the beans. Starches are broken down into simple sugars which, as the roasting process continues, are caramelized back to complex sugars giving the beans their brown color and a hint of sweetness. As the beans develop into a dark roast, the floral aromatics, fruit acids and caffeine diminish. What is gained, however, is a pleasantly bitter edge, a darker caramel taste, and a velvety smoothness. More roasting notes .