At the risk of alienating a lot of good coffee friends and placing myself in that category of observes who will most assuredly get picked last for the Barista KickBall tournament (again) this year, I’m just gonna go ahead and say it. I do not believe in the Mystique of the Chemex filter.
From the side of the Chemex filter box we read:
“Perfect coffee gives you full flavor without bitterness…. Chemex-bonded® filters filter out all bitterness, sediment, and oils: prduce a clear, flavorful coffee, without fail.”
This simple and effective marketing language has spawned the widely held belief that there is something special and unique about the fiber and construction of this particular paper that endows it with the almost magical property capturing “all bitterness”. I would appreciate an explanation of just exactly what physical mechanism present in the fibers of this revered fabric can distinguish between bitter flavor components and all the hundreds of flavor components present in coffee liquid. Of course, that is the purpose of marketing; to distinguish your product as something unique among all the similar or identical products available. Well I don’t believe it.
As any Barista experienced in dialing in pour-over brewing methods will (hopefully) tell you, reducing bitterness is a function of grind adjustment, agitation, and dwell time. The Chemex can be a real curmudgeon when it comes to dwell time. This is in no small part due to the design of the filter (in combination with the smooth and ridge-less glass). The beauty and elegance of the beaker is without question. There is no bucket of criticism in that department that will carry any water, or coffee. The exquisite hour glass shape combined with accents of natural wood and leather provide the user with an unparalleled feeling of happiness when brewing or serving. But this is no reason to imbue the Chemex with such fictitious qualities borne out of the herd mentality, or worse, superstition.
I believe the most important factor in filter paper is the fiber from which it is made. Abaca filters are excellent for strength-to-weight ratio and low occurrence of flavorful starches and tastful impurities.