The DCM decaffeination method is thought by some in the coffee industry to maintain better flavour compared to other methods. This process involves soaking coffee beans in hot water to extract as much caffeine as possible from the coffee beans. Following this, the beans are removed and methylene chloride solvent is added to bond with the caffeine. After the methylene chloride-caffeine mixture is skimmed off from the surface of the mixture, the beans are returned to reabsorb the liquid. This method of decaffeination removes more than 97% of caffeine from a batch of coffee and ensures a rich and delicious flavour.
Extensive research data has led the U.S. Food and Drug Administration (FDA) to determine that methylene chloride is safe for use in coffee decaffeination. While the FDA regulation allows for up to 10 parts per million (ppm) of residual methylene chloride, actual coffee-industry practice results in levels that are 100 times lower than this amount.