How to set a Grinder?
A grinder has two burrs that are placed on top of each other. The distance between these two burrs defines the fineness of the ground coffee. The closer the burrs are together the finer the grind.
Temperature changes will affect the fineness of the grind. It is therefore important to check the fineness of the grind a few times throughout the day with so called ‘Espresso checks’. It is recommended to have only one person a shift responsible
for the grinder.
The bottom burr is connected to the grinder and cannot be changed. The top burr is connected to the top of the grinder and can be moved clockwise or anticlockwise.
Sometimes numbers indicate the distance between the burrs, the lowest number indicating the finest setting. Move the top burr towards a higher number to increase the distance between the blades. Some grinders have instructions to indicate which direction is finer or coarser.
Check the manual of the grinder for instructions on how to change the distance between the burrs. Ensure that you hold on to the top disc when pressing down the button to change the setting to prevent it from spinning out of place.
Check the fineness of the grind by making a double espresso. Ensure there is the correct amount of coffee in the filter. If the extraction is under 20 seconds then the grind is too coarse and the coffee will be under-extracted. Extraction over 30 seconds means the grind is too fine, resulting in over-extracted coffee.
With under-extracted coffee the water filters through too easily. This can be corrected by moving the burrs closer together, making the grind finer.
Change the setting of the burrs very carefully. Move the burrs with only one click at a time. The slightest movement makes a big difference.
After adjusting the grind, dispose of the old coffee and grind some new. Grind enough coffee for two shots. Check the extraction again with the new ground coffee until an extraction between 20 and 30 seconds is achieved.