What's The Deal With Decaf Coffee?
When we think of coffee, three things come to mind; flavors, aroma, and caffeine. It’s the right combination of the three that makes us come back for more. But among us are those that would rather not deal with the effects of too much caffeine; shaky hands, anxiety, and sometimes heart palpitations. For those who would like to enjoy the different flavors of the bean rather than the accompanied psychoactive, decaf does the trick.
Caffeine is a chemical compound that acts as a defense mechanism of the coffee plant to ward off insects, pests, and undesirable germination. This chemical also has a stimulating effect on the human brain, which is part of the reason why coffee is literally everywhere. But sometimes we don’t sign up for its mind-accelerating properties, and would rather just enjoy a delightful cup of joe. So it begs the question, does decaf taste as good as regular coffee? Caffeine isn’t really known to have any flavor, but some decaffeination techniques tend to leech flavor-producing compounds alongside the caffeine.
Decaffeination gets even trickier while dealing with specialty coffee. Some people say that extracting the caffeine from specialty coffee also extracts the “special” out of it. The goal would be to remove the most caffeine with no ramifications on taste. But how does one go about isolating caffeine from a coffee bean? And which method has the least impact on flavor?
Coffee was decaffeinated for the first time in 1905 using benzene as a solvent. It’s not in practice anymore because benzene is considered a carcinogen, but the idea of using a solvent persists. Today, there are two schools of thought. A Solvent-based approach and a non-solvent-based approach. But they all start with moistening the beans to make the caffeine soluble and ready to be extracted. Solvent methods are further classified into ‘Direct Solvent Method’ and ‘Indirect Solvent Method’.
Direct Solvent Method
It’s the most popular way to decaffeinate coffee today. The solvent of choice is either ethyl acetate or methylene chloride. After the coffee beans are moistened, they’re immersed in the solvent. Once the solvent latches on to the caffeine in the coffee, the beans are placed in an evaporator to recover the caffeine-ridden methylene chloride or ethyl acetate. The beans are then washed and steamed to remove all traces of the chosen solvent. Once dried, decaffeinated coffee is roasted like any other coffee.
The presence of methylene chloride in roasted coffee is controlled to 10 parts per million because, in higher concentrations, it can prove to be quite harmful. Ethyl acetate however is considered natural and safe because it’s derived from cane sugar. Although, it’s flammable and tends to leave a distinctive odor in the coffee.
Indirect Solvent Method
Coffee beans are soaked in near-boiling water for several hours. This extracts some of the caffeine as well as other flavor compounds and oils from the coffee. The beans are then washed using either methylene chloride or ethyl acetate for about 10 hours. During this process, the solvent bonds with the caffeine. The resulting mixture is then heated to let the solvent evaporate. The solvent leaves the evaporation chamber and takes the caffeine in tow. The beans are finally reintroduced to the water from the first step to recover some of the oils and flavors. Once dried, it’s ready to be roasted.
On the other end of the spectrum are non-solvent-based methods which are rising in popularity every day. The wide majority believes that these methods are safer since they don’t employ any chemicals to aid in decaffeination. But distribution still proves to be a constraint since the most popular non-solvent methods are proprietary. The two major ones are the ‘Swiss Water Method’ and ‘Carbon Dioxide Method’.
Swiss Water Decaffeination Method
The coffee beans are immersed in hot water and introduced to a mixture of green coffee extract & water. The caffeine level in this mixture is controlled to a minimum. Since the green coffee extract is low in caffeine, it creates a system that wants to balance the caffeine levels across the board. Through osmosis, caffeine gets drawn out, thus reducing caffeine concentration in the bean. This is repeated several times, and after each bath, the remaining liquid is passed through activated charcoal which separates the caffeine from this mixture. Pioneered in Switzerland, the Swiss Water Method is efficient but it comes with a higher price tag. Unlike other methods, the caffeine is sacrificed since it can’t be isolated and sold separately.
Carbon Dioxide Method
Pressurized carbon dioxide is used in place of chemical solvents. Moistened green coffee beans are brought in contact with liquid carbon dioxide, and once it bonds with the caffeine, the CO2 is allowed to evaporate. This is an extremely effective method to extract caffeine with very low levels of toxicity, albeit a lot more expensive to carry out.
Most coffee aficionados scoff at the thought of decaf. It’s important to note that “decaffeinated” does not necessarily mean 100% caffeine-free. According to the USDA, decaf coffee only needs to be 97% caffeine-free. For many years, decaf was considered unnatural, but it’s getting better every day and is becoming a viable option for pregnant women, and people with caffeine sensitivities. Specialty coffee is still far from being legitimately decaf, but with demand on the rise, innovation is imminent. Not only in reducing caffeine content but also to alleviate the impact of decaffeination on the taste. Today, decaffeinated coffee tastes more like the real thing. Click here to try the Bunafr decaf coffee.