Green coffee is decaffeinated before roasting. This process changes the color of the green coffee: it varies from light brown (Natural and CO-2) to green-brown (MC and Swiss Water Process -SWP- decafs).
When thinking about how to make an excellent decaffeinated coffee you have to first focus on the coffee before decaffeination.
A really great decaf shouldn't taste all too differently than before it was processed for decaf.
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