The term ‘green coffee’ is one you hear a lot. But what is the exact meaning? We will tell you all about it in this article.
What does green coffee mean?
The term “green coffee” generally refers to unroasted or insufficiently roasted coffee beans. These beans have already been processed in such a way that the pulp of the coffee berry has been removed. This is done using the wet or dry methods. With the last one, a thin wax layer remains on the coffee bean. Green beans generally have a higher weight than roasted beans. This is because green beans still carry all the moisture that will disappear during the roasting process.
Swiss Water Process
The “Swiss Water Process”, a special technique for decaffeinating coffee, uses a green coffee extract. In this process, the extract is used to extract the caffeine from the unroasted green beans. This is possible because the green coffee extract is a solution containing water-soluble components with the exception of caffeine. The extract is obtained by soaking the coffee beans in hot water and then filtering them through an activated carbon filter which will remove the caffeine molecules.
Fresh beans containing both caffeine and the other components are added to the GCE solution where the pressure difference between the GCE (which is caffeine-free) and the green coffee (which is caffeine-rich) causes the caffeine molecules to migrate from the green coffee into the GCE. Because the GCE is saturated with the other water-soluble components of unroasted coffee, only the caffeine molecule migrates into the GCE; the other water-soluble coffee components remain in the unroasted coffee. The new caffeine-rich GCE solution is then passed through the activated carbon filters to remove the caffeine again, and the process is repeated. The continuous batch process takes around 8 hours to achieve the final decaffeination target.
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