Since its invention by Karl Lendrich in the early 20th century, water vapour has been used to improve the quality of green coffee. CR3’s various steaming processes are based on the Lendrich process and have been continuously refined over the past 50 years. These processes are mainly used for the gentle treatment of high-quality Arabica coffees. Coffee treated in this way contains fewer bitter compounds and develops a smoother, more refined flavour profile. The Lendrich Process, often referred to as the Lendrich Method, is a classic technique in the history of decaffeinated coffee. Although it is used less frequently today than methods such as Swiss Water or Ethyl Acetate, it remains an important example of early coffee chemistry. Developed by Karl Lendrich in the early 20th century, the process uses steam to prepare coffee beans before a solvent is applied to remove caffeine. How the Lendrich Process Works 1. Steaming (Pre-Treatment) The process begins by exposing raw (green) coffee beans to pressurized steam. Purpose: The beans swell and their cellular structure opens up, making it easier to remove caffeine in the next step. 2. Solvent Extraction After steaming, the beans are treated with a solvent, historically most commonly dichloromethane or trichloroethylene. How it works: The caffeine dissolves into the solvent and is removed from the beans. 3. Secondary Steaming Once the caffeine has been extracted, the beans are steamed again for an extended period. Purpose: This step removes any remaining traces of solvent. Because these solvents have low boiling points, they evaporate completely during the steaming process. 4. Drying and Roasting Finally, the beans are dried back to their original moisture content. They can then be roasted in the same way as any other coffee bean. The result is a decaffeinated coffee that retains as much of its original flavour as possible while removing most of the caffeine.