This past weekend, I was asked about decaf coffee coincidentally on two separate occasions. Decaf coffee is a healthy alternative for some, although it often means compromising on taste. Despite getting a lot of harsh criticism from hardcore coffee addicts and elite aficionados, decaf is an attractive alternative for those who like the essential flavor and aroma of coffee but want to avoid the physical effects of caffeine. In my tasting experience, decaf drip coffee and decaf espresso are always inferior to their caffeinated counterparts. Although I drink regular coffee, my recent conversations about decaf prompted me to learn more about the process of decaffeination.

coffee-related, Lichtenstein-inspired street art. photo courtesy of Sean Davis.

Caffeine is an alkaloid or chemical compound found in certain plants including coffee. In coffee plants it works as a pesticide but for coffee drinkers it’s a stimulating drug. Caffeine quantity varies depending on bean varietal, coffee processing, roasting methods, and brewing techniques. Decaffeinated coffee comes with a lot of drama attached to it. If you’re a decaf drinker, ignore the cultural stigma and focus on the actual decaffeinating process. It’s important for you to know how the caffeine was removed from your coffee because you may not approve of the science behind certain decaf methods. There are four different, currently used methods to removing caffeine in coffee. All the methods use water and are done prior to roasting when the beans are still green. Two of the methods use chemical solvents to help remove caffeine.

The Processes of Decaffeinating Coffee:

• The Direct Method –

Beans are steamed for about 30 minutes, which opens up their pores allowing them to receive solvents. They are then rinsed repeatedly for several hours with either methylene chloride or ethyl acetate—both FDA approved chemical solvents. The caffeine-filled water is thrown out and the beans are steamed again for several hours, removing any solvents. This method directly exposes the beans to chemicals and makes the beans lose their natural oils.

• The Indirect Method –

Beans are soaked in hot water, which extracts caffeine and natural oils. They are then completely removed and either methylene chloride or ethyl acetate is introduced to the water and then heated, which allows for both caffeine and solvent to evaporate. Beans are put back into the water, which is free of caffeine and solvents, in order to absorb its original oils and flavors.

• The CO2 Method –

This method is chemical-free, using supercritical carbon dioxide—a state that makes CO2 both gas and liquid like—to extract caffeine. Dampened beans are placed in a pressurized compartment with carbon dioxide. The gas-like CO2 enters the beans, removing them of their caffeine. The caffeine dissolves with the liquid-like CO2 and is filtered out, which can later be recycled into caffeinated beverages like soda. Beans are then left to dry naturally, with much of their oils and flavors left intact throughout the whole process.

• The Water Method –

This method is completely chemical-free. There are two official water methods—the Swiss Water Process (SWP) and the Mountain Water Process (from Mexico). Both use water as a natural solvent to extract caffeine from coffee beans. Beans are soaked in hot water and then filtered through (the Swiss method uses a charcoal filter), trapping the caffeine molecules and releasing the beans. The coffee flavored but caffeine free water is either reintroduced to the decaffeinated beans to give them their flavor back or (as with Swiss method) used again as water to filter out caffeine in a new batch of beans. This process allows for flavors to be saved, while discarding the majority of caffeine. Companies who use these methods will proudly mention it.

Although coffee is both roasted and brewed at high temperatures, and therefore unlikely to have solvent remnants, I still prefer a non-chemical decaf process. No method guarantees the total removal of caffeine from coffee beans—small traces of it will remain—but most decaf coffees are about 97-99% caffeine-free. There’s always a loss of flavor during decaffeination but buying coffee from companies invested in quality, who label their decaffeinating methods, is a good place to start your search for delicious decaf coffees.

Like any processed food, decaf coffee comes with a lot of controversy. It’s up to you to know what works best for your body and to be aware of what kind of coffee you’re putting in to your system, regardless of whether you drink regular or decaf. If you’re a health conscious Coloradan looking to decrease your caffeine intake, I would actually recommend trying black teas like Earl Grey and Masala Chia or just using less ground beans and more water when brewing coffee.

Javaher Nooryani