How Coffee is Decaffeinated

There’s nothing like a hot cup of coffee to set the tone for your entire day, but there is a time and place for caffeine. Whether you’re craving a hot beverage in the late afternoon or a digestif after a delicious meal, decaf coffee offers the best of both worlds without any stimulating effect to keep you awake late into the night. Unbeknownst to many coffee drinkers, coffee is always decaffeinated in an unroasted state. Caffeine occurs naturally in coffee, so most diehard enthusiasts believe that the process of decaffeinating goes against the grain and results in a weaker cup of coffee. There are a few concerns when it comes to decaffeination, but the most worrisome is the sheer amount of chemicals that occur naturally in coffee to produce distinct tastes and aromas. Decaffeinating is rumored to affect those original chemical concentrations to result in an unsatisfactory cup of java, but we’ve done our research into how coffee is decaffeinated to prove that decaf coffee is still a tasty alternative.

 Organic Chemical Solvent Method

The two most popular solvents for naturally decaffeinating coffee include ethyl acetate and methylene chloride. The beans are soaked in boiling water from 30 minutes to several hours in order to make them swell and keep caffeine extraction easier. Either chemical solvent is used to further the caffeine extraction process by circulating and undergoing distillation. The beans are then rinsed with water again and vacuum-dried before being roasted.

Ethyl acetate (EA) is often found in fruits or vegetables, and is considered one of the few indirect solvents used to decaffeinate coffee. When we say indirectly, we mean naturally! Ethyl acetate is used to wash coffee beans for up to 10 hours. During this process, those chemical molecules selectively bond with caffeine molecules before being heated to the point of evaporation.

Methylene chloride (MC), otherwise known as dichloromethane, can extract approximately 96 – 97 percent of caffeine in green coffee beans. Unlike ethyl acetate, this solvent does not appear to occur naturally in the environment and is often made from methane gas or wood alcohol. Widely used throughout Europe, this chemical solvent has become synonymous with decaffeination and is thought to maintain flavors better than any other processes.

Carbon Dioxide Method

Similar to direct solvent methods, carbon dioxide (CO2) utilizes extraction to retain the flavors and aromas of green coffee. When compressed, carbon dioxide behaved like both a gas and a liquid to combine selectively with caffeine. Steamed beans are bathed in this compressed solvent to remove caffeine through charcoal filtering. This method differs from other chemical solvent or water methods in that it retains the flavor components throughout the complete process. Methods vary from company to company, but specialty extraction vessels operate at high atmospheric pressures to circulate compressed carbon dioxide throughout pre-moistened beans. This solvent is widely popular because it boasts a relatively low-pressure critical point and is naturally abundant. As a result, CO2 absorbs about 96 – 98 percent of original caffeine.

Water Method

At one time, the water method was considered detrimental to the final flavor and aroma of coffee. Since then, decaffeination processes have improved to supersaturate green coffee beans without losing their original essences. Some manufacturers claim small-batch decaffeination, in which they remove caffeine in a gentle, chemical-free way. Around the world, this popular process is also known as the Swiss Water method. In this process, water is employed to remove caffeine within a vessel. Combining water with coffee extract that has already been decaffeinated to an extent, green coffee beans are circulated within the extraction battery for a predetermined amount of time before being rinsed and dried for roasting.

Ultraviolet on the Horizon

Our journey ends with the latest method to hit the market. Light absorption is a cutting-edge process that measures caffeine content in coffee. Caffeine molecules absorb light at different wavelengths in the spectrum, and the results can be used as quantifiable data to determine accurate concentrations. Spectroscopy is currently used in association with carbon dioxide decaffeination processes. Although there is much to learn about the ultraviolet light process, we hope that it will reduce the risk of sensitivity to caffeine and its side effects. Preliminary reports are resulting in poor flavor for now.

Verdict: How Coffee is Decaffeinated

Although researchers have found that 400 milligrams of caffeine a day is safe for most healthy adults, unchecked amounts of caffeine can result in migraines, insomnia, irritability, upset stomach, or rapid heartbeat. Regardless of whether it’s processed by chemical solvents, water, carbon dioxide, or ultraviolet light, decaffeinated coffee may be the smartest solution to keep you satisfied at the end of the day. CoffeeCow carries a remarkable selection of decaf coffees and teas to suit any taste. Explore our inventory today! If you have any questions about how coffee is decaffeinated, please feel free to contact us for further or additional information.