Roasting coffee at first seems deceptively easy. Pop some raw, green beans into an oven and in a little while, take them out all brown and roasted. In fact, roasting coffee is a developing science and far more complex than it first appears.
The aim of a Master Roaster is to produce coffee that has been roasted to an ideal flavour point. This is a point at which the flavour has developed sufficiently to create a complex balance of body and intensity with a bittersweet chocolaty character. It’s a tricky undertaking and requires that the roaster taste the coffee constantly. Too light a roast and the coffee will taste grassy and hemp-like. Too dark and it begins to lose its natural sweetness as the sugars are caramelized. If it is roasted even darker still, it actually turns the natural wood-fibre in the beans (cellulose) into charcoal. This results in a charred, ashy and very unpleasant espresso.