Mocopan Coffee’s Jared Chapman explores the four variables of grinder calibration that impact over- and under-extracted coffee and why coffee is a game of constant tasting. Taste. It’s what we’re all about in the coffee industry. Striving for that sweeter, more delicious cup of coffee. This has led to a lot of work being put into understanding the many variables that affect the flavour we end up with in the cup. With more information out there on variables like particle size distribution and total dissolved solids (TDS), it can be overwhelming for a budding barista to start to understand the basics without getting confused by all the detail.