|Blending and roasting|
BlendingBeyond a shadow of a doubt, to achieve a good espresso, the blending stage is of fundamental importance.
For a proper coffee blend, several aspects of the raw material must be taken into account: whether we are handling Arabica or Robusta, washed or natural coffees, beans from South America, Africa or Asia; the percentages and, obviously, the quality of green coffee.
RoastingInside the roasting machine, our magical “green gold” is heated to a temperature ranging from 200 to 230°C. To guarantee a homogenous product, this must be done in a very consistent manner.
During the roasting process, depending on origin, the beans lose 18-20% of their weight and increase in volume by as much as 60%. This gives rise to the formation of the aromas in the coffee and, indeed, several hundred such aromas can arise. The texture of the bean changes from hard to rather crumbly and oils start to appear on their surface. The color of the beans change depending on the temperature reached: the more they are roasted (running the risk of burning the coffee), the darker they become and the more bitter the flavor. The more rapidly the beans are cooled off, the better aromas are preserved.
The length of the whole process can vary depending on the kind of roasting chosen. On average, it should last about 15 minutes, although an expert roaster can judge what is exactly the “right moment” to end the cycle, even by listening to the “music” produced by the beans.