If there's a heavy amount of foam and oil floating on the top of the coffee (which you can really only get a significant amount of from an expensive machine like the Gallia for $1500 or a french press) that is where almost all of the polyphenols and major health compounds are
Make no mistake, in the right proportions coffee is a health supplement/food because the coffee bean is actually the fruit or literally seed of the coffee plant. Learned that about two years ago.
Modern medicine more appropriately called Modern Drug Medicine points to coffee as a culprit for certain issues like high blood pressure but refuse to acknowledge (because of their inherent darkness and lack of good) the other causative factors or the fact that inappropriate use and moreso, poor quality and rancid chemicals in processed coffee plus sugar are the major causes of the heart issues, plaque atherosclerosis etc etc