THE BREW DOG BLOG
Why Grind Size Matters
Whether you have a grinder at home, or grind you coffee at a local store or café, the importance of the grind size of your coffee is hard to understate.
The name of the game in coffee is extraction, and in order to produce the best results, we need a level of consistency. Why? Because this is chemistry, people. You’re a scientist now.
In order to know where you must adjust your brewing recipe, you need to be monitoring all the variables, and have your extraction/draw-down time be consistent, as this is essential for a stellar cup.
The main reason we ask what you’re brewing your coffee with when you ask us to grind it in store is so we know how fine to grind the coffee, so that it extracts in the best way possible via the method you are using.
The Fines
If you are using your coffee for espresso then you would need a very fine grind. If you were brewing with a Chemex, however, you’d need a much courser grind than for espresso, closer to a medium course grind size.
This is because coffee will extract differently based off of the method being used. The insane amounts of pressure used by an espresso machine requires a lot of resistance, hence the extremely fine grind. The Chemex, on the other hand, relies on gravity to run water through the coffee grounds, thus needs a courser grind.
If your coffee were to be ground too fine for your Chemex, your pour over would run minutes long, and taste like bitter, bitter, bitter defeat. Over extraction at it’s worst. But not fine enough, and the end result is just as undesirable.
The Courses
If your coffee were too course (or with too large a particle size) for your Chemex at home, you’d end up with a weak, insipid, and sour cup of coffee. It would be very under-extracted, essentially.
Finding the right balance in particle size is essential for crafting a great cup of coffee. A few microns in the other direction and the difference in taste is noticeable by a trained palate. A few minutes over a certain drawdown time for a pour over is also noticeable.
The Draw Down
Regardless of how and what you’re brewing, all you are trying to do is get a balanced extraction for the best possible tasting cup of coffee you can manage.
This is done by monitoring all your variables, as mentioned above, and the best place to start is with your grind size. Water temperature, pulse pouring, scale or no scale, timer or not; all of those in my opinion are secondary to having a consistent grind size.
You could have all the rest of the ingredients, and be monitoring all the rest of the variables, but if you had an inconstant grind, no matter what you did, that coffee wouldn’t quite taste the same — or even how you’d like— each time you brew it.
To sum in all up: because an even extraction equals a good tasting cup of coffee, having an even grind will help give you an even extraction. There is, of course, room for human or mechanical error, but assuming that doesn’t happen, an even grind is your best bet to great tasting coffee.
