Decaffeinating your coffee

January 23, 2019

Decaffeinating your coffee

Here at Cotswold Coffee Roasters we procure our customers a seasonal Decaf which has been carefully selected by our various suppliers.


From Peruvian to Kenyan, like all coffee these beans begin their life caffeinated before they undergo a series of phases to remove the alkaloid stimulant that is the caffeine. This process essentially separates the cellular laters of the raw green bean by swelling its size with water and steam. When the bean achieves the required size, a concentrated green coffee extract is applied which dissolves out the caffeine content using a carbon filter. Approximately 8 hours later and the coffee bean is caffeine free and is then left to dry naturally before they are ready for packing. This decaffeination process is commonly referred to as the Swiss Water Process (SWP).

Decaf (raw green on left in the image below) is usually considered tricky to roast. This can be attributed to a few reasons such as the caffeine (raw green on right) extraction slightly degrading the cellular make up of the bean meaning they take on more heat during roasting. The processing method also removes more of the silverskin (outer bean layer) which is more commonly known as chaff. This layer restricts or protects a bean from taking on excess heat during the roast. The chaff then peals off and is expelled from the outer later as the bean expands rapidly to double its green size.

The images below show our roasted seasonal decaf on the left when compared with a roasted caffeinated sample on the right. You can see that for the decaf roast, the chaff has more colour, is darker, and has less of it remaining in the inner middle fold of the bean.

Making sure our decaf beans are treated with a less aggressive heat throughout the roast, ensures we develop the flavour and translate this into the cup for our customers to enjoy no matter what time of day.

If like us, you are interested in a more detailed description of the history of decaffeination processing methods over the last 100 years, there is an additional blog available here

Leave a comment

Comments will be approved before showing up.