Even if your grinder cost a small fortune, it might not reflect that in your espressos if you are not properly adjusting your grinder. So here are the steps to getting those adjustments right, along with some tips from Enrico, our master roaster, on getting the most out of your coffee.
First, there are two adjustments you can make to your grinder: coarseness of grind, i.e., whether your coffee will be fine or coarse, and the amount of coffee that falls into the filter holder with each dose (if the grinder offers this as a setting).
Grind adjustment differs slightly with each model. For most models, you have to turn a large wheel surrounding the grinder, located where the coffee tank and the grinder motor meet (see photos below). Directions are usually on or near the wheel to indicate which side you should turn for a coarser or finer grind.
If your grinder doesn’t have a rotating paddle, the same principles still apply for the adjustments. The coarser the grind (thicker), the faster the coffee flows from your espresso machine. The finer the grind (thinner), the slower the coffee will flow.
When you buy a new grinder, it is usually unadjusted. So, first things first, you will want to find the ‘0 point’, or the point at which the burrs meet. To do this, run the grinder continuously (without coffee in it) until you hear a change in the sound it makes (usually a sharp sound).
When you hear this change in sound, stop the grinder immediately.
To get the perfect grind for espresso, you will have to grind the coffee finely. Generally, this is about a ¼ of a turn (for a rotary paddle grinder).
For espresso, your grind should be like the constancy of sand (see photo below). Unfortunately, there is no exact science on what the grind size should be exactly, so experiment through trial and error, and be patient. Grind small amounts of coffee at a time, and tweak the grind level between each grind, until you get the perfect espresso.
Of course, the grind is only one factor in a successfully extracted espresso. You also have to adjust the amount of water for your espresso shots, and the two variables have to work in unison. So, you will have to repeat the process of adjustments to the grind if either of these variables change.
Generally, a single espresso shot should contain about 7 to 9 grams of coffee, while a double shot should contain 16 to 18 grams.
To achieve this perfect amount, you have two options. The first and the easiest, is to use a scale to accurately measure your doses. You can adjust the quantities while weighing so that it is perfect, and it saves a lot of time in making the perfect shot, unless you're a real professional grind spotter (like Enrico).
The second option is to do it visually. If you've ever ground your coffee for an espresso machine, you should have a fairly good idea of how the coffee dose and fineness should look.
Again, whichever option you choose, it will still require some trial and error! You should run the espresso until you get the perfect crema and flow. Of course, you may have to readjust the grind settings to really nail it.
The portafilter is a good visual cue for how much coffee to use per dose. All filters have a line, on the inside, which marks the approximate point to where the coffee should rise when tamped (see photos above). This is a great starting point!
Each grinder model has their own adjustment mechanism, both for grinding and dosing. So be sure to check out the instructions, and you will learn what you need to know!
During the trial-and-error phase, we recommend you throw away all of the first ground dose after each adjustment, so you only have freshly ground coffee in your new test dose.
You may have to spend some time adjusting the grinder, but once it's done, you won't have to mess around with it much anymore! But yes, a little bit. For a residential grinder, micro-adjustments will be needed about every 2 to 3 months. For a coffee shop serving large volumes, you should make these minor adjustments a few times a week, or even daily (depending on volume). Make sure to check regularly to see how well your espresso is extracting.
It also depends on how sophisticated your grinder is. Coffee beans are living things, so its properties can change a great deal with just humidity and heat. Some grinders automatically adjust to these changes, but others do not. As always, just be sure to keep a close eye on how your espressos are pulling!
Our article on choosing the right espresso grinder may help you with your next shopping trip. Check it out right here!
