T for gentle drum roasting

TRADITIONAL CRAFTSMANSHIP

Roasting coffee is a traditional craft and is crucial for the taste of the coffee. Our master roaster creates a unique roasting profile for each coffee, which emphasizes the individual character of the coffee. Very complex chemical reaction processes take place during roasting when heat is applied. During this process, sugars and amino acids are recombined so that around 1,000 new aromas and chemical compounds are formed in each individual cell. This makes coffee one of the most aromatic foods of all and has significantly more aromatic substances than wine.

GENTLE DRUM ROASTING

We roast our coffees in a small traditional coffee roastery on beautiful Lake Constance. The Genio drum roaster from Johannesburg is ideal for fully developing the coffee aroma. We only roast small batches of 4-5 kg with roasting times of between 13 and 21 minutes. The roasting time depends on the desired roasting result. The final temperatures range from 200°C for light filter coffee roasts to 220°C for very dark roasting results. The coffee receives the energy required for roasting indirectly through contact with the externally heated roasting drum and the heated air. Once the roasting process is complete, the coffee must be cooled quickly. This is done with cold air on cooling sieves and completely without water.  

QUALITY THROUGH ROASTING

Roasting plays a decisive role in the quality of coffee. We roast our coffees over a longer period of time and with comparatively little heat so that the flavors can develop clearly. Only the deliberate, subtle fruit acids, which contribute to the character of our coffee, are retained. We roast our espressos a little longer than our filter coffees. In this way, unwanted acids disappear almost completely and ensure the typical strong espresso taste. Overall, drum roasting is a complex and demanding process that breaks down the aggressive chlorogenic acids that irritate the stomach wall in the best possible way. First, the pale green green green coffee, which smells of hay, is placed in the preheated roaster. The heat dries the remaining moisture out of the beans and the color of the beans gradually turns yellow. After around 7 to 10 minutes, the color changes to brownish and a spicy smell develops, reminiscent of popcorn or freshly baked bread. The newly formed gases in the beans (carbon dioxide and monoxide) cause the beans to increase significantly in volume.

THE "FIRST CRACK" AFTER 15 MIN

After around 12 to 15 minutes, the pressure in the beans is so great that the cell walls of the coffee bean burst open audibly. This moment is known as the first crack. From now on, the full spectrum of flavors unfolds. The fruit acids are broken down, sugar caramelizes and the cell structure is weakened. During this time, the master roaster must observe the process very closely, as he only has 2 to 4 minutes until the beans are charred. During this time, the color of the roasted coffee changes from light brown to medium brown to dark brown to black-brown. Once the roasting process is complete, the coffee falls out of the roasting drum into the cooling sieve. Here, the hot coffee is cooled by cold air and an agitator. The beans then pass through a "destoner", in which any small stones that may be present in the green coffee are removed. The roasted coffee is then packaged and needs around 2 weeks to degas the CO2 that has been produced. Only after this "resting time" of around 10-14 days can the coffee develop its full aroma.