TRADITIONAL RATHER THAN INDUSTRIAL ROASTING
Drum roasting is the traditional method of roasting many coffee beans at once. In the history of coffee, people roasted the valuable beans in pans, on hot stone or in ovens. However, drum roasting is the only type of roasting that, on the one hand, allows us to keep an eye on the raw beans. On the other hand, we can determine the temperature exactly to the degree and thus avoid undesirable roasted aromas.
THE MAILLARD REACTION
When we read the green coffee and put it in the drum, it changes color with increasing temperature. Experts call the process the Maillard reaction. The green bean first turns yellow, then light brown. When the temperature reaches around 220 degrees, the bean breaks because all the liquid has evaporated. After that, by the way, the coffee only develops strong roasted aromas as needed for espresso. This process releases a lot of natural chemicals that determine smell, taste and appearance.