Despite being a bean, the most common form of coffee we’re familiar with is powdered. To brew any coffee, we first grind the beans to powder. If you step beyond instant coffee and drip coffee, you’ll be faced with an array of different coffee grind sizes to explore.
Why do we grind coffee anyway? It all has to do with how coffee releases its flavors and aroma. Most of these flavor and aroma compounds in coffee are insoluble in water, so the bean has to be crushed to help release these compounds. This plays an important role in how your final cup will taste.
Why Does Coffee Grind Size Matter?
Grind size is simply how big or small your coffee particles are. The smaller the particles, the finer the grind size and vice versa. Different brewing methods require different grind sizes. This is because of extraction- how much coffee is pulled from the beans into the water. Overextraction gives you a bitter and overly strong cup of coffee while under-extraction leaves you with weak and thin coffee.
The ultimate goal of choosing the correct grind size when brewing coffee is to optimize extraction. Under-extraction happens when the grind size is too large or coarse and the brewing time is too short. This gives you acidic, sour coffee and no one wants that. Overextraction is a result of using grounds that are too fine and gives you bitter, ashy coffee.
No matter how expensive your coffee is or how advanced your brewing machines are, if you don’t get the extraction right and use the correct grind size, you risk ending up with a lacklustre cup.
Coffee Grinds and Brewing Methods
The grind size you need to pick depends on what brewing method you use and how much time it takes to brew. If you’re just starting to experiment with grind sizes, pay attention to where you buy your whole beans. Coffee platforms like Era Of We that focus on sustainability, farmer relations, and transparency are your best bet for high-quality, ethically-grown coffee. Here are the basic grind sizes you need to know and which brewing methods work with each one:
Starting with one of the rarer grind sizes, an extra-fine grind is flour-like and only used to brew Turkish coffee. You’ll need a Turkish coffee grinder and brewer to use this grind size. When brewing Turkish coffee, the hot water is in contact with the coffee grounds for a very short period of time so an extrafine grind is needed to optimize extraction.
This is the standard size for most pre-ground coffee. A fine grind looks similar in size to granulated sugar. This grind size is best for making espresso and for an AeroPress with a short brewing time.
Similar in size to common salt, a medium-fine grind size is ideal for brewing methods like a Moka pot, AeroPress, and certain pour-over brewers with cone filters. A Moka pot is quite similar to an espresso maker, and it also requires a small grind size to slow down the flow of water through the coffee. This prevents under-extraction and ensures you get a balanced cup.
A medium grind has the consistency of regular beach sand. This grind size is what most novices are familiar with. This size is recommended for drip coffee brewing. Pour-over coffee makers with conical filters can also use a medium grind, where the smaller size of the coffee grounds holds water for longer to prolong the extraction time. Brewing with an AeroPress also works with medium grind size.
This grind size is similar to coarse sand in size and consistency. A medium-coarse grind is ideal for brewing in a Chemex and other pour-over brewers. A Chemex uses a paper filter that is quite thick and this requires a grind size that will let water pass easily so that it doesn’t over-brew.
A coarse grind is about the size of sea salt. This is a good size for a French press, where the water needs to pass freely through the coffee grounds. The grind size also needs to be large enough that it doesn’t pass through the mesh filter when the plunger is pushed down.
This is the largest coffee grind size you can find. The size can be likened to rock salt. The large grounds are slow to absorb water and are perfect for cold brew coffee that takes 24 hours to brew. The long brewing time accommodates the slow water absorption to give you a smooth brew.
How Can You Grind Coffee at Home?
Grinding coffee at home is a great way to get more involved in your coffee consumption and ensure you have fresh coffee for a superior cup every time. Most of us are used to buying pre-ground coffee but switching to grinding coffee yourself can dramatically elevate your coffee experience. There are two ways you can grind coffee at home: using a blade grinder or a burr grinder. Both types of coffee grinders are available in manual or electric variants.
A blade grinder has blades like a food processor that rotate and grind coffee beans. The rapidly moving blades chop up the beans but ultimately give you an inconsistent grind. The heat and friction from the spinning blades can also overheat the beans, affecting the final taste. For these reasons, experts advise you to use a burr grinder instead.
A burr grinder works by applying pressure evenly across the beans using two rough discs. A conical burr grinder is the preferred option since a flat burr grinder can cause bits of coffee to get stuck within the teeth/burrs. The discs rotate at a low speed to crush the beans between them giving you a smooth and consistent grind with no residual heat production.
Burr grinders can be more expensive than blade grinders but they’re worth every penny. They can be small, portable, and easy to use. The consistent grind size is the biggest advantage. A consistent grind size reduces the risk of under- or over-extracting your coffee.
You can make things easier for yourself by investing in a coffee maker that comes with a grinder, like those listed here. Relying on pre-ground coffee can be convenient but there’s nothing like the control of grinding your own beans. Not only does your coffee stay fresh longer, but you get to customise your coffee just the way you like it. It’s a great way to understand more about coffee and get to know it on a new level. It may seem daunting at first, but give it a try and explore the endless possibilities of freshlyground coffee.