For home use I was suggested to purchase a Mazzer grinder in order to grind beans for use in semi-automatic espresso machine. How does that help make better espresso?
One does not need a Mazzer or any other commercial grinder for use at home. Mazzer grinders are for commercial use and have disc type flat burrs. The disc burrs spin at a very high speed of 1800 to 2000 r.p.m. to grind fine coffee. At that speed, excessive heat is generated which alters the quality of coffee. Purchase of a Mazzer grinder for home use is like buying a size 12 shoes for size 7 feet! For home use, there are a few conical burr grinders available.