Creative Bioscience Green Coffee Bean Pure Extract, 60 Veggie Capsules. Green Coffee Bean Pure Extract may help burn fat fast, but the active ingredient isn't caffeine. In fact, each serving contains only 20 mg of caffeine. For reference, an 8-oz cup of generic, brewed coffee contains 95-200 mg of caffeine. The apparent fat-fighting function comes from the Chromogenic Acid found in unroasted coffee beans. If you are sensitive to stimulants, this is a diet supplement that may not give you "java jitters" or raise your heart rate