I did some blind cupping today, with a friend and two Aeropresses (one with the new Able Disk Fine metal filter, and the other with a standard AP paper filter). We sampled three very different coffees:
1) Ethiopia Gedeo Worka (Klatch)
2) El Salvador San Emilio (Compass)
3) Kauai Coffee Estate Reserve (dark roast)*
Grinder: Breville Smart, set to the midpoint of the percolator/filter range
Brew ratio: coffee:water = 1:16 (10g grinds to 160ml water)
Brew temperature: just off the boil (boiling point of water is 203F at my elevation)
Brew time: 2 minutes (inverted)
Agitation: initial stir plus another stir after 1 minute
Pressing: 20-30 seconds
Somewhat to my surprise, there were small but noticeable differences in the cup. The metal-filtered AP brew was more acidic and fruitier than the paper-filtered AP brew. The paper-filtered brew was slightly more bitter and less balanced than the metal-filtered brew. This held across all three coffees. I was able to distinguish between the filters in our blind taste tests, and correctly identified the filter in all but one case. I preferred the metal-filtered brew across the board.
Pressing resistance from the metal filter is slightly higher than the paper filter. There is more sediment in the metal-filtered AP brew, but it is not objectionable (nothing like French press).
Thumbs up from this reviewer.Able Disk FineInverted brewing, natch*gift from a well-intentioned friend