Coffee Brewing 101: Coffee Grinding
The whole goal in brewing coffee is to extract the perfect amount of flavor from the coffee grounds, not too much, not too little.
We discussed the process of extraction in the first post of this Coffee Brewing Basics series. Now lets examine how coffee grind size impacts extraction and coffee brewing.
At the end of this discussion I will give my practical approach to coffee grinding using the grinder I use every day.
Coffee Grinding: Blade vs Burr Grinders
One of the MOST COMMON mistakes when it comes to making coffee at home is using the wrong type of coffee grinder!
Blade grinders (which are really spice grinders) have a blade that chops coffee beans. These grinders are the cheapest and easiest to find. The main problem is inconsistent grind size with some huge pieces and some very fine particles. This leads to the worst of both worlds–overextraction of the small particles AND underextraction of the large particles.
On the other hand, burr grinders crush coffee beans between ceramic or metallic disks (burrs). This technique results in consistent grind size that you can control and change. The grind size corresponds to the space between the burrs. The result: MUCH better coffee!
Since you’ve taken the time to learn about extraction and the science behind coffee brewing by reading this far you need a burr grinder. I recommend a few coffee grinders and discussed this topic in more detail in this previous post.
Coffee Grind Size and Extraction
A properly extracted coffee tastes delicious. Coffee that is underextracted has a sour, acidic, salty taste–yuck! On the other side of the spectrum, overextracted coffee is just bitter–also yuck!
Coffee grind size is one of the major factors that affects extraction.
Too fine of a grind size = overextraction.
Too coarse of a grind size = underextraction.
Now things aren’t that simple. Coffee brewing is the interplay of coffee grind size, brewing time, brewing technique, and water temperature. So the optimal coffee grind size depends on brewing time and brewing method! Some methods expose the coffee to water for a short time and require fine coffee grounds while course grind size is optimal for methods that take longer.
3 Basic Coffee Grind Sizes
For simplicity we will talk about 3 basic grind sizes: Coarse, Medium, and Fine. There are obviously sizes in between these 3 categories. Some authors and coffee experts will talk about up to 11 different coffee grind sizes. However, I feel like that is pretty deep into the weeds and you can make some kickass coffee following just the basics!
- Looks Like–Ground Peppercorns or Sea Salt
- Brewing Methods–French Press, Cold Brew, Cupping (coffee tasting)
- Baratza Virtuoso Setting–#30
- Looks Like–Sand
- Brewing Methods–Electric Coffee Maker, Pour Over, AeroPress
- Baratza Virtuoso Setting–#15
- Looks Like–Flour or Very Fine Table Salt
- Brewing Methods–Espresso, Moka Pot
- Baratza Virtuoso Setting–#5
Baratza Virtuoso Grind Size Guide
I personally use the Baratza Virtuoso Coffee Grinder but the less expensive Baratza Encore is also a great choice. Both of these grinders offer 40 different grind sizes that you can adjust very easily (0 = finest grind size and 40 = coarsest grind size). Either of these coffee grinders would be an excellent choice to elevate your at home coffee experience.
Here is the practical, actionable approach to coffee grinding use these Baratza grinders. I will give you the grind size # that I use for each coffee brewing method. The grind size # is essentially the same between the Virtuoso and Encore grinders. Obviously if you use a different brand of burr grinder these numbers would differ but you can still use this as a general guide.
#15 Pour Over (Hario, Kalita Wave)
#15 Drip Coffee Makers
#30 French Press
#30 Coffee Cupping/Tasting
Now that you have a better understanding of extraction and coffee grinding you are well on your way to making better coffee at home! In the next post we will discuss the coffee/water ratio, which impacts the strength of the coffee.
Here’s to drinking better coffee! Cheers friends!