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Die Wissenschaft hinter dem Rösten: Was in der Bohne passiert

The science behind roasting: What happens inside the bean

The science behind roasting: A look inside the coffee bean

When coffee is roasted, the green, rather inconspicuous raw coffee beans are transformed into the aromatic, dark treasures that we love so much. But what exactly happens in the bean during this process? Let's take a journey together into the world of aromas, chemistry and physics that will reveal the secret behind a perfectly roasted coffee bean.

The roasting process: A complex chemical reaction

Roasting coffee is much more than just heating the beans. It is a carefully controlled process that requires precise timing and temperature to develop the desired flavors. During roasting, the beans undergo several chemical reactions. The most important of these is the Maillard reaction, named after the French chemist Louis-Camille Maillard. This reaction between amino acids and reducing sugars creates the complex flavors and colors that are characteristic of roasted coffee.

The phases of roasting: From the first crack to the cooling

During the roasting process, the beans go through several phases. The first critical phase is the "First Crack", a moment when the beans start to make noise and puff up. This is a sign that water evaporation and expansion of the beans are beginning. After the First Crack, the aromas become more intense and the beans develop their characteristic brown color. Depending on the desired degree of roasting, the process can end shortly after the First Crack or continue until the "Second Crack", where the beans acquire an even darker color and a more intense aroma.

The role of temperature: precision leads to perfection

Controlling the temperature is crucial for the roasting result. Temperatures that are too high can burn the beans and produce bitter flavours, while temperatures that are too low can inhibit the development of flavours. Experienced roasters know how to precisely control the temperature to find the balance between acidity, sweetness and bitterness that makes for an excellent coffee.

This is what you can take with you

Roasting coffee is both an art and a science. It requires an understanding of the chemical reactions that take place within the bean, as well as patience and precision to unlock the beans' full potential. The next time you enjoy a sip of your favorite coffee, think about the wonderful journey the beans have been through, from the roasting drum to your cup. The science behind roasting is the key to the rich aroma and flavor that makes coffee one of the world's most popular beverages.