The Patented Processes for Coffee DecaffeinationJuly 13, 2023

While many of us are unable to function without the caffeine in our morning cup of coffee, not everyone can tolerate its stimulating effects. Thus, decaffeinated coffee is a blessing for those who crave the flavor but seek to limit their caffeine intake.

Ludwig Roselius, a German coffee merchant, is credited with inventing the first commercially successful decaffeination process. The story goes that when one of his coffee shipments got drenched in seawater, Roselius noticed that the beans had lost much of their caffeine. Roselius further refined the process, which resulted in a patented method of decaffeination involving the use of benzene as a solvent (U.S. Patent No. 897,763).

Health concerns around benzene eventually led to its replacement with safer solvents such as methylene chloride or ethyl acetate (U.S. Patent No. 2,391,981), both of which are still widely used in certain decaffeination processes today.

A solvent-free method known as the Swiss Water process was introduced in the 1930s (Swiss Patent No. 169,031). This process involved soaking coffee beans in water, filtering the solution to remove the caffeine, and then soaking the beans again to reabsorb essential flavor compounds. The Swiss Water process was later refined and commercialized in the 1980s (U.S. Patent No. 5,208,056).

In the 1970s, a method involving the use of supercritical carbon dioxide (CO₂) was developed (U.S. Patent No. 4,260,639). In this method, the caffeine dissolves in the heated and pressurized CO₂ while other compounds that contribute to the flavor are largely insoluble and remain in the bean. This method proved to be highly efficient while retaining the coffee’s flavor and avoiding organic solvents.

Looking ahead, the next generation of decaffeinated coffee may involve coffee plants that are gene edited to include a mutation in one or more genes of the caffeine biosynthesis pathway (U.S. Patent Application No. 2021/0238618) such that no caffeine is produced by the plants. As we look forward to the future of decaffeinated coffee, it’s exciting to think about the new ways we can enjoy our beloved beverage, sans caffeine.

Brian D. Keppler, Ph.D. is a registered Patent Agent in the MVS Biotechnology & Chemical Practice Group. To learn more, visit our MVS website, or contact Brian directly via email.