The most important step to producing excellent coffee is grinding your beans, and grinding them properly. When coffee is ground, aromatic compounds and CO2 are released, which leave the air smelling amazing (hopefully!) Once ground, coffee absorbs moisture and begins to deteriorate, which is why it’s always best to grind it fresh every time. And NEVER store your coffee in the fridge.
Terrible coffee is virtually always the product of badly ground coffee beans, and we’re going to run through a quick guide on how to make sure you know how to troubleshoot bad coffee and turn it into great coffee.
Blade Grinder vs Burr Grinder
There are two main types of coffee grinder available. Widely used in home applications, blade coffee grinders spin a metal blade round to smash the coffee beans into pieces. These pieces vary wildly in size, and because of this are very difficult to brew a decent cup of coffee with.
Burr coffee grinders are much more accurate. Ceramic or metal burrs spin together and ‘shave’ layers off the coffee beans, creating particles of coffee which are much more uniform in size. Burr grinders are available as handheld manual units, or electric appliances. All grinders in cafes and restaurants are burr grinders.
How Can I Improve the Flavour?
There’s two things to look out for here. If you’ve ground your beans wrong, you’ll either be OVER extracting or UNDER extracting the coffee. Let’s have a look at what that means.
Over extraction is just as it sounds, extracting too much flavour from the grounds, leaving a bitter, empty taste in the cup. This happens when you’ve ground your coffee too fine, or left it brewing for too long. Think stewed tea.
Under extraction is where not enough flavour has been extracted from the ground coffee. This is noticed by a sour, acidic flavour in the cup. The body of the coffee is thin and watery. This is easily spotted on an espresso machine by the rate at which the coffee is pouring from the portafilter handle into the cup – too fast and gushing.
How to Fix it
If your coffee is over extracted, you need to use coarser grind setting on your grinder.
Under extracted coffee is fixed by adjusting your grinder to a finer grind setting.
For full-immersion brew methods (Clever dripper, Cafetière) you could alleviate over extraction by brewing your coffee for a shorter amount of time, or a longer amount of time for under extraction.
Always tweak your grinder settings gradually. Once you find the sweet spot for a particular brewing method, make a note of it for future reference.
Common Grind Sizes
Different brew methods require different grinds, dependent on the amount of time the ground coffee is in contact with the water. Nailing the grind size will ensure a perfect brew every single time. Here’s a little list of common grind sizes for reference.
We offer all our coffees as whole bean and ground. Our ‘fine’ setting is ground for espresso or Moka pot (please specify at checkout), our ‘medium’ setting is somewhere between medium and medium fine, and is a general grind suitable for most applications. Our ‘coarse’ setting is for cafetière with a 5 minute brew time.
To Sum Up
If your coffee tastes sour, salty and acidic, grind it finer.
If your coffee is bitter and devoid of body and mouthfeel, grind it coarser.
Don’t use a blade grinder, use a burr grinder.