Caffeine is naturally occurring in over 60 types of plant species; the most common being coffee Arabica and coffea Robusta, tea and cocoa beans. Robusta coffees have about twice as much caffeine as Arabica coffees.
Decaffeination removes nearly all the caffeine from the beans. It is carried out while the beans are still ‘green’, before they are roasted.
How much caffeine is in decaf coffee?
Decaffeination removes about 97% or more of the caffeine in coffee beans. A typical cup of decaf coffee has about 2 mg of caffeine, compared to a typical cup of regular coffee, which has about 95 mg of caffeine.
The Decaffeination process
In 1906, Ludwig Roselius, a German coffee salesman, patented the first decaffeination process for commercial use which involved steaming green coffee beans with water and various acids and then using Benzene as a solvent to dissolve the caffeine. Roselius’s method is no longer in use because Benzene, an organic chemical compound, has associated health risks.
All decaffeination processes take place when the coffee is in its green state, before it is roasted.
Various methods exist, the two most common processes are Swiss Water Process (SWP) and CO2 Method.
Swiss Water Process
The Swiss water process may be a more desirable method since it is a chemical-free decaffeination process. To begin the decaffeination process, a batch of green coffee beans are soaked in hot water to dissolve the caffeine. However, sugars and other chemical components that create the flavor and aromas of coffee we love can also dissolve in water.
So, how do you decaffeinate coffee without solvents and retain the flavor profile of your favorite beans?
After soaking, the water from the first round of green beans is passed through a charcoal filter. Caffeine is a large molecule and gets trapped in the filter while the sugars, oils and other chemical elements in coffee that impart flavor and aroma pass through and stay in the water to create what is called Green Coffee Extract. A second batch of green coffee beans is then soaked in the Green Coffee Extract (flavorful but caffeine-less water) to remove caffeine. However, this time around, since the Green Coffee Extract is saturated with flavors but not caffeine, the beans will not lose or gain any flavor and will lose caffeine to the Extract. Now, the still flavorful water contains caffeine and is run through a filter again to remove the caffeine, making the water once again a Green Coffee Extract. The extract is used repeatedly for up to ten batches of beans. One cycle for one batch of beans, starting from creating the GCE to decaffeinating a batch of beans, takes approximately ten hours.
Carbon Dioxide Method
The carbon dioxide method, technically known as subcritical carbon dioxide extraction, involves soaking unroasted coffee beans in highly pressurized carbon dioxide that is compressed to two hundred times its normal atmospheric level. The pressurized carbon dioxide removes the caffeine from the beans.
This method can be performed on a very large scale and is therefore the most widely used method for commercial-grade, less exotic coffee found in supermarkets. Mechanisms can be found in a decaffeination plant implementing the carbon dioxide method.
The method can be summarized in several steps:
1. Green coffee beans are soaked in water.
2. Caffeine removal occurs in an extraction vessel suffused with CO2.
3. Decaffeinated beans at the bottom of the vessel are removed, dried, and roasted.
4. Recovery of dissolved caffeine occurs in an absorption chamber.
Unroasted beans go down from the small vessel at the top and as they enter the large vessel in the middle, carbon dioxide is compressed onto the beans, extracting the caffeine, leaving decaffeinated beans to fall through from the bottom vessel.
We offer Decaf Colombia Coffee in store which is 100% Arabica beans from Colombia. It undergoes another Decaffeinated process (Sugarcane decaffeination) and roasted to medium dark level, with full body, natural sweetness of caramel, milk chocolate and black berry flavour. This decaf coffee is best enjoyed in espresso or filter coffee (black coffee and milk coffee).
Thanks to its wide range of locations, climates and altitudes Colombia can meet demand for coffee throughout the whole year. The Sugarcane decaffeination process magnifies sweetness and acidity, producing an excellent decaffeinated coffee.
Sugarcane decaffeination utilizes a naturally occurring compound, ethyl acetate (EA) to decaffeinate coffee. The EA used in this process is derived from molasses (a byproduct of sugar production). Since EA is naturally-occurring, the process is labeled as “naturally decaffeinated.”
The EA process is relatively simple. The coffee beans are moistened with water and EA is circulated throughout. The EA binds with the caffeine in the bean and extracts the caffeine while leaving most of the other flavor compounds. After the desired caffeine level is reached, the EA residue on the beans is removed by steaming them.
Are you a decaf coffee lover? Let us know what decaf process your coffee undergoes. We would love to hear.