Next we come to the grind size. Looking at the extremes, if you were to brew a cup with a bean you had just sliced in half, and then brew a cup that with a bean you pulverized into a fine powder, if all other factors were held constant, the cups would taste DRASTICALLY different. This can be seen also with much smaller variations in grind size, and even with grind consistency. This brings us to grinders, and what could possibly be a VERY long conversation (I’ll try to keep it to a minimum). There are two main types of grinders, blade and burr grinders. Blade grinders are the ones usually sold in grocery stores, they have 2 blades that spin around and break the coffee up that way. Burr grinders have 2 sets of circular burrs that spin and grind the coffee as it tries to pass through.
Burr grinders are MUCH more consistent since the coffee has to be a particular size to pass through the burrs, and if it is too big, the burrs keep breaking it up until it is at the specified size. The reason a consistent grind size is important is for the same reason listed above in the hypothetical example, if you have some coffee that is pulverized, and some that is left in big chunks, water will extract flavors from it at differing rates, giving a less than ideal brew. Considering that burr grinders are usually much more than blade grinders, it's not always reasonable to spend the money on a burr grinder. Luckily, there are some tips and tricks to get the best from a blade grinder. First is to gently shake the grinder as you are grinding (make sure you hold on to the top!!). This should help to keep things moving, and prevent one area from being pulverized more than another. Another tip is only grinding in 3-4 second increments, then stopping for a few seconds, then repeating this until the desired grind size is achieved. Happy Grinding!