The direct contact method of decaffeination is a process in which chemicals (other than water) are used on green coffee beans (milled but not yet roasted) with the goal of dissolving and extracting the caffeine.
The Direct Contact Decaffeination Process
A direct contact decaffeination method uses chemicals in direct contact with the coffee beans and also may utilize supercritical carbon dioxide, which is carbon dioxide stored at a high pressure and temperature so it may be used as a decaffeination agent.
Steaming the Coffee Beans
The direct contact method typically involves steaming green coffee beans for ½-hour and then rinsing them repeatedly with ethyl acetate or methylene chloride for approximately ten hours.
After the solvent is drained from the coffee beans they are steamed again for another ten hours with the goal of removing any residual solvent.
Coffee and Espresso Brewing Tips
Decaffeinated coffee is a great way to reduce caffeine withdrawal symptoms and allows people to continue to benefit from coffee’s health benefits compared to complete stopping consumption. For tips on brewing the perfect cup of coffee see our section on Coffee Brewing. You can also read detailed coffee flavor profiles of gourmet coffee and instructions on preparing Espresso Drink Recipes.