How is decaf coffee made?
First, what is decaf coffee, and how is it made?
It all starts with decaffeination—a meticulous process that seeks to delicately strip coffee beans of their caffeine while preserving their distinctive flavors. Various methods have been developed over the years to accomplish this, each with its own unique approach.
Today, there are three decaffeination techniques that are most commonly used in the coffee industry:
#1 Swiss Water Process
This method, renowned as a chemical-free and environmentally friendly approach to decaffeination, consists of four basic steps:
1. Soaking the beans in water to extract soluble components.
2. Passing the water through a carbon filter to remove caffeine.
3. Drying the beans and preparing them for roasting.
4. Recycling the caffeine-infused water for the next batch of beans.
The Swiss Water Process is perhaps the most sustainable approach to decaffeinating coffee beans, while also being highly effective. That said, some aficionados might argue that since the same water is recycled between multiple batches, the mixed oils and compounds might dilute the coffee’s subtler notes.
#2 Direct solvent method
Also known as the "traditional" or "conventional" method, this process involves the use of chemical solvents to extract caffeine from green coffee beans. Essentially, the green coffee beans are steamed to help dissolve the caffeine.
While this method has been used for decades, advancements in technology have led to stricter regulations and the development of safer solvents.
Many of these modern solvents are designed to fully vaporize in the high temperatures of the bean roasting process, meaning the chance of ingesting any harmful chemicals is extremely slim.
#3 Carbon Dioxide (CO2) method
Employing pressurized carbon dioxide, this method relies on CO2’s unique properties to selectively extract caffeine from the coffee beans. Here’s how it works:
● Green coffee beans are soaked in water and loaded into a sealed container, exposing them to high-pressure (up to 1,000 lbs per square inch) liquid carbon dioxide.
● The carbon dioxide interacts with the coffee, binding with the caffeine molecules, and drawing them out.
● The caffeine-rich carbon dioxide is filtered, separating the caffeine from the gas.
● The purified carbon dioxide is recycled, and the caffeine-free beans are ready to roast.
This method is widely renowned for maintaining the integrity of the coffee's flavor profile during the decaffeination process, although it is far more expensive and less commercially available than other methods.
