Why You Should Brew Coffee With a Scale
The benefits of using a scale when brewing coffee far outweigh (pun intended) the snide comments or associations with snobbery that may get put upon you. The primary reason for using a scale is that it allows precision and repeatability.
Mass > Volume
Physics tells us that when it comes to measuring things, mass is much more accurate than volume. This is particularly clear when measuring flour. Many baking recipes specify whether the flour is supposed to be sifted or not; this is because sifted and unsifted flour take up different amounts of space. Weighing by volume not only leads to possibly using too much or too little flour, but it also means that every time the recipe is made, the outcome may differ.
This is also true of coffee. All coffee beans are not created the same way—they are different shapes and sizes. And, different ways of brewing coffee require that you use different grind sizes, which take up different amounts of space. These different grind sizes do not pack the same way. When measured volumetrically, smaller grind sizes have smaller air pockets than larger grind sizes.
If you are just getting into using a scale, the industry standard water-to-coffee ratio is 16:1—16 mL of water (1 mL of water = 1g) to 1 gram of coffee. So, if you are making one mug of coffee, you might use 15 grams of coffee and 240 grams of water.
Recommendations
Pourover Coffee
The scale that we personally love is the Acaia Pearl. We cannot recommend it enough. It has a rechargeable battery, a built-in timer, and just looks nice on the counter. However, it is a bit pricey. So if you are looking for a cheaper option, we suggest looking for a gram scale that weighs to tenths of a gram, like the Hario Coffee Scale. This will allow even more exact measurements.
Espresso
If you only have a scale that rounds to whole numbers, we suggest weighing coffee beans in such a way that just tips the scale, so to speak. For example, if you want 15 grams, add 14 grams of coffee beans, and then add one bean at a time until the scale changes to 15.
As James Freeman says, “If you’re going to buy good coffee and attempt to make it well, why be approximate?”