Many people drink coffee for the enjoyment and relaxation that it brings. However, the caffeine content, which helps keep us awake, often prevents us from drinking beyond the morning.
That’s why a lot of people swear by decaf coffee, which offers all the other benefits with next to no caffeine – perfect for the afternoons!
But it begs the question – how is the caffeine actually taken out of the coffee? Well, there are a few methods that coffee roasters use to reduce the amount of caffeine in their products.
Because caffeine is water-soluble, all methods of decaffeination use water in some way. However, producers can’t use water alone, because that would also remove a lot of the flavour compounds, sugars, and proteins from the beans.
Some methods involve the use of solvents and chemicals, while others are more natural and solely rely on water and filters. All these processes are carried out while the coffee is still green (before roasting).
Swiss Water Process
The Swiss Water Process is a chemical-free way to produce decaf coffee. This means it is completely organic - which is why we use this method at The Bean Alliance.
It works by soaking the beans in water, which dissolves many compounds within the coffee, including caffeine. This water is then separated from the beans and passed through a special filter.
As the caffeine molecules are too large to fit through the filter, they are left behind whilst the rest of the components pass through. After this, the water is returned to the beans where they reabsorb it, along with any sugars and proteins that were taken out with the caffeine.
This results in a bean that is still bursting with delicious flavour, ready to be roasted.
Carbon Dioxide Process
This is a newer method of processing. Generally, it is utilised by brands that produce very large quantities of coffee because it’s quite expensive.
Similar to the Swiss Water process, it begins by soaking the green beans in a tank of water. Following this, carbon dioxide (CO2) is added to such a high pressure that it becomes a liquid.
In this state, the CO2 is capable of extracting and dissolving the caffeine (but no other compounds) in the water.
After the water is removed, it can be depressurised, which separates the water and CO2, the latter becoming a gas again, leaving the caffeinated water behind.
The CO2 can be reused countless times, and the water is discarded.
Lastly, there are two types of decaffeination that involve the use of chemical solvents. These methods are extremely popular, with large brands such as Starbucks using them for most of their decaf products.
Again, the beans are soaked in water which draws out most compounds. From here, the water is either separated from the beans to be treated (indirect-solvent), or the solvents are added directly to the beans (direct-solvent).
There are a few types of solvents, but they all target caffeine and leave most of the other compounds behind. The treated water, along with the flavour compounds, sugars, and proteins are then naturally reabsorbed by the coffee beans.
Any remaining solvents are completely burned off during the roasting process, which therefore makes these coffees 100% safe to drink.
So now you know how decaf is made! Try drinking coffee made with different methods and see if you can taste the difference. We’ve got plenty of Australian Certified Organic, Fairtrade, Swiss Water Process coffee for your brewing pleasure.