Like those used in other decaffeination processes, methylene chloride is a solvent that is used to bond with and strip caffeine molecules from the green coffee seed. The KVW MC process first uses hot water to extract caffeine and other solubles from the coffee seeds, and then the seeds are removed from the water. Methylene chloride is then added to the water solution, and it bonds with the caffeine; because MC is not miscible with water, it is easily removed from the solution along with the bonded caffeine, and the coffee seeds are re-submerged in order to absorb their soluble compounds. The United States Food and Drug Administration has stated that MC is safe for use in decaffeination processes, and is harmless to humans in consumption of 10 parts per million (ppm) or less. Coffee decaffeinated using this method has been shown to contain a fraction of that safe amount.
For more information about coffee production in Mexico, visit our Mexico page.