Marcel Hackler and Vinzenz Särchen first crossed paths during their bachelor's studies in Bio- and Nanotechnology in Iserlohn, Germany, where they discovered a mutual passion for coffee that blossomed into a close friendship. Marcel went on to earn a master's degree in Sustainability Economics and Management in Oldenburg, Germany. His deepening love for coffee led him to work as a barista, offer barista courses, and eventually found Käthe Kaffeerösterei GmbH. His hands-on experience in the coffee industry provides invaluable insights into the coffee value chain in this work. Vinzenz pursued a more academic route, completing a master's in Biochemistry and Molecular Biology in Kiel, Germany, and a Ph.D. in Tumor Immunology in Frankfurt am Main, Germany. He currently works at the University Medical Center Rostock, Germany. Vinzenz's interest in coffee extends to its biological effects and biotechnological processes, drawing on his educational background to enrich this collaborative work.