The earliest commercial decaffeination process involved steaming coffee beans in a salt water solution and then soaking them in the toxic chemical benzene to dissolve the caffeine.
Due to health concerns, benzene has now been replaced in the "direct method" with different toxic chemicals, ethyl acetate or methylene chloride. Since ethyl acetate can be derived from fruits and vegetables, this coffee is often advertised as "naturally decaffeinated!"
In the "indirect method," also known as the "water method," the beans are soaked in water, treated with ethyl acetate or methylene chloride and then re-soaked in the same water to reabsorb essential oils.
One toxin-free decaffeination process is the "charcoal method," which is similar to the water method but uses a charcoal filter rather than chemical solvents to remove the caffeine. The "carbon dioxide" method, in which beans are steamed and soaked in carbonated water, also uses a carbon filter.
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