The primary difference between wood-roasting and conventional roasting (gas or electric) lies in the speed at which the internal temperature of the bean itself rises i.e. how quickly the temperature of the air in the roaster is transferred to the bean. Conventional roasting is used nowadays to speed up the roasting process and reduce cost … not to enhance the final product.
Our beech wood-fired roaster slowly raises the temperature of the air in the roaster to between 500-525°F, significantly lower than conventional roasters that can quickly raise the temperatures of the air up to 840°F. The consequence of roasting within this lower range is a much slower transformation (known as the Maillard Reaction
for you chemistry geeks) of the bean as it rises in temperature. This results in a roasting time that takes three to four times longer than traditional methods, but which allows us to retain many of the natural compounds by preserving more of the lipids, or “flavors”, within the beans.
This slow roasting process results in coffee that is lower in acidity and higher in body.