At home, I use a domestic Sunbean burr grinder and will generally clean my grinder after every 5 kilos of coffee I put through it. As you can imagine, my grinder gets quite a good work out and that will usually mean I clean my grinder every fortnight. You might want to clean your grinder more in line with a monthly or bi-monthly cycle - it all depends on how fussy you are and how much coffee you consume.
To clean my Sunbeam EM0480 grinder, here is what I do;
- turn off the power at the wall and disconnect the power plug for safety.
- empty the coffee bean hopper (that's usually not a problem as the hopper is always 'near empty'. You can dump your unused coffee beans into a container for use later).
- Depending on your grinder configuration, separate the top burr from the bottom burr.
- Since the hopper is completely plastic, with no metal parts, I will dunk it into warm mild soapy water and give it a good gentle clean, to remove any coffee oil build up.
- Be careful with moisture and water around the burr set, since depending on the grade of steel used, it could be open to rust if it gets wet. Under normal use, the coffee oils will provide protection from moisture (that's my opinion and possibly not fact).
- Clean the burr set with a dry toothbrush. Pay attention to the underside of the top burr set, as any built up coffee grinds will affect your grind sensitivity settings, generally givving you a finer grind than you expected at a particular setting.
- Give the burr set housing a good general clean with the toothbrush and shake as much coffee grounds out of the housing that you practically can.
- Dry the hopper and reassemble the burr set and hopper.
- fill with coffee beans
- enjoy a coffee from a fresh clean grinder - it almost always feels better with a feeling of accomplishment.
Depending on your finances, you may decide to replace your burr set with a fresh burr set. My burr set is 4 years old and would have seen approximately 500 kilos of coffee, and while it grinds slower now than it probably should, I have not replaced the burr set with a new set. A replacement burr set for the Breville EM0480 runs at $100, of which I would prefer to put towards a new grinder at year 5 (which is when the factory warranty expires).