Caffeine is a naturally occurring chemical present in plants such as coffee plants, where it serves as a defence mechanism to repel insects. The caffeine in coffee plants is what gives coffee beans their stimulating properties but not their flavour.
High-quality Arabica coffee beans are typically 1% caffeine by weight, whereas Robusta beans have twice that amount. At Volcano, we use Arabica beans in our decaf coffee.
In order to create decaffeinated coffee, an extra processing step has to be added to the coffee’s journey to extract the caffeine from the beans. There are multiple ways this can be done – by using chemical solvents or more natural compounds.
There are 4 main methods of producing decaf coffee; the CO2, Swiss Water, Methylene Chloride and Ethyl Acetate method– the two that do not use chemical solvents are the CO2 and Swiss water method.
At Volcano, we use the CO2 method as it only uses 2 natural compounds: water and carbon dioxide.
The CO2 method
For the CO2 method, the coffee beans are soaked in water and then liquid CO2 is forced through them in a highly pressurised container so that it can dissolve the caffeine. The caffeine soaked CO2 is then moved to another chamber where it is depressurised and allowed to turn into a gas again, leaving the caffeine behind. The CO2 is then captured and recycled or reused again.
CO2 is efficient at extracting caffeine but leaves the flavour components alone, so it does not affect the quality or taste of the coffee.
The CO2 method is not only a more natural and efficient method but also a zero waste method. The CO2 is cycled through the coffee over and over again within the process and the only waste in this process is solid caffeine which is used in other industries and for other purposes - so it doesn’t create any residual waste.
Our new limited edition half caff coffee blend, Half Steam is made up of a 50:50 blend of decaffeinated and caffeinated coffee.
Half Steam has a medium roast profile with rich notes of cacao, orange and brazil nut. This blend of Peruvian and Brazilian beans is suitable for drinking all day long, without having to compromise on taste, quality, or a great night’s sleep.
Want to try Half Steam? Buy it here.
A note from our speciality coffee roaster, Claire:
“The caffeine in the Decaf portion of Half Steam is removed using only two ingredients; water and carbon dioxide. This is an extremely effective, fully natural process - no chemical solvents are required.
Also, the CO2 method doesn't disturb the flavour compounds in the coffee beans; meaning you don't have to compromise on taste to enjoy a lower caffeine cup!”