Many people drink coffee each morning for its caffeine content. Drinking a cup or two of coffee each morning helps people wake up and start their day. However, many choose to drink less coffee because of its caffeine content. For these people, decaf coffee is a great choice for them, but there is a lot of stigma behind it due to the process of using chemicals to remove the caffeine.
What many don’t realize, however, is that there are several ways to decaffeinate coffee, and while chemicals can be used, there are much cleaner ways that also preserve the taste and health of the coffee. In fact, there are four main ways, and I will go over them.
Indirect-Solvent Process
In this process, the coffee means must first be soaked in boiling water for a few hours, which removes the caffeine, as well as some of the oils, from inside. The beans are then removed and soaked in a bath of methylene chloride for ten hours. After those ten hours, the liquid, which has bonded with the caffeine molecules, is evaporated, and the beans are placed back into the original water, where the oils and flavor are absorbed back into the beans.
Direct-Solvent Process
This process is similar to the Indirect-Solvent Process. However, instead of soaking in boiling water for hours, the beans are steamed for half an hours before being placed into the methylene chloride solution for ten hours. After those ten hours, the solution, which has removed most of the caffeine, is drained, and the beans are steamed again to clean them of the solution.
Swiss Water Process
Invented in Switzerland, the Swiss Water Process involves two batches of beans. The first batch is soaked in hot water, removing the caffeine and all the flavor of the coffee. The beans are then removed from the water and discarded, since they no longer contain any caffeine or flavor. The water is drained through a charcoal filter, which blocks caffeine from leaving but allows all the flavor molecules to pass through with the water.
This water is now saturated with those flavor molecules. The second batch of green beans is placed into the water and then heated. The same process happens as with the first batch, except this time, since the water is saturated with the flavor, the flavor from within the beans stay in the beans, while the caffeine is removed like before.
The resulting beans now contain 99.9% caffeine but have retained their full flavor.
Carbon Dioxide Process
In this process, beans soaked in water are sealed in a steel container, where liquid carbon dioxide is forced into it at 1000 psi, removing the caffeine. The CO2 is then removed from the container the depressurized, where is is cleaned and later reused. The resulting beans have had most of their caffeine removed.
In my opinion, the Swiss Water Process is the superior method of removing caffeine. It is also, unlike the Carbon Dioxide Process, much cheaper. Unlike the solvent methods, it does not require the use of chemicals like methylene chloride or ethyl acetate, so it is much safer. It also retains all of the flavor and health benefits of the coffee. I do not drink a lot of decaf coffee, but when I do, the Swiss Water Process is definitely my preference.