Roasting—also known as “refining”—gives coffee beans their flavor profile. It creates a consistency that can be developed during the subsequent grinding process. Roasting coffee beans brings out a variety of aromas and gives coffee its unique flavor. A single bean contains between 300,000 and 400,000 cells.

Roasting refers to the dry heating of raw coffee beans. Three factors play a particularly important role in roasting:

• the highest temperature
• the heat curve
• the time

The most important event in the roasting process: the "first crack"

During the roasting process, the coffee bean increases significantly in volume due to the gases produced and the evaporating water, which cannot escape. After about nine minutes, the pressure becomes so great that the cell walls of the bean burst and the water vapor can escape. By this point, the color of the bean has changed from its previous pale green color to a yellow/brownish color. Once the “first crack” has occurred, the roaster must be extremely vigilant. Now the coffee beans begin to develop their aromas and form their typical flavor characteristics. Acids are broken down piece by piece, the cell structure decomposes, and sugar caramelizes inside.

The longer the coffee is roasted, the more acids are broken down. At the same time, more and more roasting aromas develop, giving it a much stronger and more bitter taste. Those who prefer a more individual taste opt for shorter roasting times, thereby enhancing the coffee's own flavor, its “body.”

The roasting time plays a decisive role in the taste of coffee. The degree of roasting varies depending on the heat input and duration of roasting. The individual roasting levels of coffee beans are shown below:

• Cinnamon Roast:

  Probably the lightest of all roasts. A light brown color ensures pronounced acidity and complex aromas. This state occurs immediately after the "first crack".

• City Roast Plus:

  The medium brown bean reaches its perfect roast point approximately two minutes after the “first crack.” There are slight roasted flavors, but it is still very acidic.

• Full City:

  The bean is already slightly dark brown. This takes just under four minutes after the “first crack” has started. The coffee bean now smells spicy and pungent and tastes bitter and roasted. The acidity recedes into the background.

• Continental (French Roast):

  Shortly before the second crack, the bean is already dark brown. An oily consistency emerges and the flavor is dominated by strong roasting aromas.

• Dark French (Heavy):

  After the first half of the second crack, the caramelized sugar breaks down. The bean becomes lighter and lighter. The flavor concentrates entirely on roasted and bitter aromas.

• Spanish Roast:

  At the end of the second crack and afterwards, the bean is blackish brown. It shines and has hardly any nutrients left. The taste is slightly burnt and can only be perceived through a few bitter substances and roasting aromas. Roasting coffee can be a true craft. Roasting masters train daily on new variations, learning more and more about the diversity of coffee aromas and how to bring them out in the best possible way. We have summarized the best ones for you in our article Top 10 Roasters.