Grinding

The right grind and its uniformity are the basis for a delicious cup of coffee. One word that can capaciously characterize the importance of grinding is “resistance”. It describes how coffee and water interact during contact. Let’s take a look at the main points that relate to grinding using the example of making coffee in the V60 funnel:

● When making coffee, water will seep through the coffee tablet. Paper filters add resistance. The holes in the paper are very small, and they are so numerous that if you add up their total surface area, you get one hole of a fairly large diameter – about 2 cm.

● If you use too fine a grind, as possible, you will most likely clog the paper filter with “dust”. The pores in the paper are very easily clogged with small coffee particles, sometimes so much that they completely stop the flow of water. Therefore, it is highly discouraged to use rotary cutter grinders, which produce an excess of fine particles.

● The proportion of coffee particles small enough to completely settle inside the 20 mm hole in the paper filter is less than 1% of the total ground coffee by weight. Research has shown that if we measure coffee particles by quantity rather than mass on a typical grind profile suitable for brewing a V60 funnel, then for every particle above 100 microns there are 100 million particles below that size. This is an order of magnitude greater than the number of pores in the paper filter. One thousand microns equals 1 millimeter.

● The coarser you use the grind, the less fine particles you get. A good analogy for this is a carpenter cutting a wooden plank. The more pieces a carpenter cuts into pieces, the more “dust” he produces. Fine particles during grinding are for you the equivalent of “dust”. Each grinder is “dusty” and all small particles tend to migrate to the bottom layer of the coffee pill