What’s the difference between a domestic coffee grinder and a commercial coffee grinder.
The short answer – everything.
Domestic coffee grinders vs commercial coffee grinders.
There are basically 2 types of coffee grinders that one would find on the market for domestic or commercial use.
The first which is only for domestic use, that have blades (sometimes referred to as propeller) and the other types of grinders that have grinding burrs. The burr type coffee grinders can then either have flat or conical burrs.
Grinders with blades (or propeller grinder)
These are the cheaper coffee grinders that are found in supermarkets. They are called blade grinders or propeller grinders because that is what the grinding blades look like. They don’t actually grind the beans, they chop the beans into smaller parts.
These grinders have a huge disadvantage in that the coarseness of the final grind cannot be pre-set or accurately be predicted. You would have to keep checking by eye to see if the grind is what you want and pulse the on/off switch to achieve the desired grind. This type of grinder is best used for filter or plunger coffee but not for espresso.
There are no commercial blade (propeller) coffee grinders, these are purely domestic.
Grinders with burrs
Grinders with burrs can either have flat burrs or conical burrs. These flat or conical burr grinders can then either be ”doser/ portion“ or “on demand” grinders. And these grinders can then also be domestic or commercial.
Flat burrs are just that – its 2 flat burrs that can be adjusted either closer together or further apart to result in either a finer or coarser grind. Conical burrs can achieve the same result but the 2 burrs have a difference shape. For arguments sake lets say that the grind size is achieve by bringing a male burr closer or further away from a female burr.
The biggest advantage of both these burr types is that the grind size or coarseness can be pre-set so that everything you grind your beans the coffee particle size is the same. This is so important because if the particle size of your ground coffee is not the same you will have a different extraction for each particle when extraction your espresso.
We’re just over half way now so hang in there.
Regardless if the grinder has flat or conical burrs, the grinder can either dispense “grind on demand” or “doser/ portion”. Then the “grind on demand” can be pre-set or manual.
Doser/ portion grinders first grind coffee into a dispenser before you manually dispense either a single or double shot into your porta filter. The amount of coffee dispensed into your porta filter can be set by manually adjusting the amount of coffee in each portion of the dispenser. Doser/ portion grinders can either be domestic or commercial. A disadvantage of this type of grinder is that in order to dispense an exact amount of coffee you will have to grind enough coffee so that the dispenser is partially filled with ground coffee – this can result is a waste of coffee or ground coffee becoming stale.
So now we get to the “grind on demand” grinders. The major and most important advantage is that the grinder will only grind the exact amount of fresh coffee that you will require per shot. In my opinion this is the way to go for domestic as well as commercial use.
In the most basic and entry level “grind on demand” grinder like the Rancilio Rocky , which has its own problems, you are not able to set the grind time. So you can grind on demand but the grinder is unable to stop grinding when the desired grammage is reached. You must manually pull the porta filter away from the grinder when you “think” you have the correct grammage.
Please rather spend a little bit more and get something like the Compak K3 Touch for your domestic grinder. Now you are entering programmable “grind on demand” grinder territory where your coffee is always fresh and your grinder will automatically dispense only the required amount directly into your porta filter.
Below are examples of the various variations. Please, its not that complicated, just takes a bit of reading to understand what’s best for you.
This Isomac Macinino Professionale Inox is an example of a domestic conical burr “grind on demand” grinder while the Mazzer Kony Electronic is an example of a commercial conical burr “grind on demand” grinder.
I’ve just got to mention on this OTT twin hopper, self-tamping, ceramic flat burr, grind on demand, stepless grinder – the La Marzocco Swift. The way this machine tamps is a whole other discussion.
As with espresso machines it is important to speak to the right people and make sure that you understand your purchase and that it suits your needs.