Many people think the best way to improve the taste of their coffee is to get better coffee beans. There is no arguing that getting a better quality of coffee will make things better, but there is actually something you can do that will have an even larger impact, and that is choosing the right grinder.
Grind Immediately Before Brewing
One thing you need to be aware of with coffee is that it's flavors are at their peak about 24 hours after roasting, and then it is a steady decline from there. Having your coffee pre-ground further speeds up this process, because more surface area of the coffee is exposed. Ideally you would grind your coffee immediately before brewing. (Spoiler alert: be sure to keep reading, b/c not all grinders are made equal)
The Truth about Blade "Grinders"
There are two major types of coffee grinders out there: Blade & Burr. A blade grinder will typically cost $20 or less. It is about the size of a mason jar, and you typically load it by removing the cap, which exposes the blade. You drop in your coffee, replace the cover and press a button to whip the blade around, and chop up your coffee. Keyword there: CHOP. I did not use the word grind. The result is an extremely inconsistent grind with some of the coffee in large chunks, and others pulverized to a fine powder. When you use this “ground” coffee in your brewer, the large chunks will add little flavor, and the pulverized power will be over extracted and contribute only bitterness. The result will taste horrible. But I can assure you, since you will be thinking this is how I am "supposed" to brew coffee, you will force a smile on your face (even though the coffee sucks) and in your head you will question why all those coffee snobs in their scarves insist on grinding before brewing.
Don't fear, there is a way, and that way is using a Burr Grinder. Where a blade grinder uses a spinning blade to chop the coffee, a burr grinder uses two grooved pieces of metal, one stationary and one that rotates, to grind the coffee in to consistent pieces. To visualize how this works, make your hands into fists, give yourself a fist pump, but leave your fists together (try this with another person and see who can last the longest). Next, rotate one of your fists. Where the two fists (or burrs) come together, that is where the coffee would be getting ground. The benefit of a burr grinder is that you will get a consistent grind for whatever brew method you intend to use (french press, pour over or espresso), and you will taste the difference. The downside with burr grinders, they can be expensive. As with anything, you can spend a lot of money if you want to, but the typical entry price for a burr grinder is $50 or higher (and sometimes much higher).
Given what we have gone over, I have a few recommendations on how you can Step Up Your Coffee Game. First, here is how I would rank the grinding options:
Option 1: Burr Grinder
Option 2: Pre-Ground Coffee
Option 3 (if you are desparate): Blade Grinder
I have also linked a few burr grinders at three different price points below. I have previously owned the Breville Smart Grinder, and it did a great job, and it looked attractive on the counter. My only complaint, is that it would clog if I was grinding a very dark roast for espresso. I currently own the Rancilio Rocky Grinder, and it is a tank. The build quality is excellent, the grind is consistent with a very wide range of grind choices, and it has never jammed on me. I have not personally used the Cuisinart, but 4 Stars on 5,800 reviews doesn't lie.
Less Expensive Option
Clay & Eric