Figure 3. Upper panel: The particle size distribution as a function of number (cumulative) of physical particles (shown in blue) and the integral of this data (shown in grey), yields 99% of the particles with a diameter of 70 μm or less.

The fine particular cutoff is depicted as a purple dashed line. Middle and lower panel: The grind profiles of the four coffees examined here. The cumulative number and surface area contribution are shown in solid and dashed lines, respectively. The Tanzanian, Ethoipian, El Salvadorian and Guatemalan profiles are shown in black, purple, red and blue, respectively. Data modes i-vi are included for visual aid: i - 14.3, ii - 27.4, iii - 282.1, iv - 13.0, v - 27.4 and vi - 256.9 μm.