Toasted, key points

Through the roasting process we transform the metabolic composition of the beans, producing both physical and chemical changes through the application of heat.

This energy penetrates and breaks the molecules that make up the cells, modifying their components (sugar, proteins, etc.) and developing the aromas and flavors that the grain has acquired during its months of development.

This heat energy is transferred from the drum to the interior of the grain by mixing conduction and convection. In a process known as Pyrolysis or commonly, cooking.

 In the graph we can perfectly observe the phases of the roasting process, these are classified into three phases; Drying ( green color ) , Maillard ( yellow color ) and Development ( gray color ).

 Drying; First the bean begins to gain temperature, which causes a loss of moisture and physical changes in the coffee bean. We can divide this phase into two;

•     The first begins with loading the drum of our roaster and ends when the coffee bean is balanced in temperature with the ambient temperature inside.
•     Once the turning point is reached , the drying phase continues producing a visual change in the grain, causing it to change its color from green to yellow (dry wheat).

Normally the first phase ends around 160°

Maillard ; series of chemical reactions produced by the introduction of heat energy to the latticework, causing the breakage of its molecules.

    The second major phase of this process known as Maillard Reactions takes place immediately after the beans have turned yellow. In this phase, the molecules of the cells inside the grains begin to break down and the grain, in addition to releasing water vapor, increases its size.

 This phase ends at around 200, when what is known as First Crack occurs .

Development ; The time elapsed between the first crunch and the extraction of the beans from the drum, this will define the flavor and aromatic characteristics of our coffee.

This phase takes the coffee beans to the end of the roasting process and varies greatly depending on the roasting profiles, the roaster and the connotations that he wants to give to his coffee in a cup.

It is important to note that the coffee beans develop throughout the roasting process and that minimal changes in temperature, airflow, rotation speed, etc. They can lead to big changes in the final aromas and flavors.