Brewing Method Determines the Best Coffee Grind
True coffee lovers know that the single best way to improve the taste of your coffee is to grind it fresh just before you brew it. The flavor in brewed coffee comes from the essential oils, sugars and proteins present in the coffee bean. Roasting green coffee beans develops and releases those oils and sugars, and brewing the beans extracts them from ground coffee. However, the oils and aromatics in coffee don’t wait for water to start fading. In fact, coffee beans start losing their flavor as soon as they’re done roasting. Grinding the coffee hastens the flavor loss by exposing more of the bean surface to the air. Ergo, you can preserve the coffee flavor in your beans by grinding them just before you brew them.
If you snoop around among coffee experts and connoisseurs, you’ll hear a lot about the right way to grind your coffee. One of the first things you’ll learn is that a $20 bladed coffee grinder is Not Good (TM). This is accepted as gospel truth by the most dedicated of the coffee snobs, and there’s a lot of background to support the contention. In fact, a burr coffee grinder — which is guaranteed to be more expensive than a coffee grinder that whirls the beans around and crushes them into powder — does produce more evenly ground coffee and does it without heating up the beans. Heating up the beans can result in some flavor loss, so burr grinders do produce better ground coffee than bladed grinders. Conical and disc coffee grinders are more expensive still, but result in the most even coffee grounds and the best coffee. However, the difference between pre-ground coffee and grinding your own coffee — even with a cheap coffee grinder — is so profound that it would be silly to pass up the flavor boost because you can’t afford to spring for a high-quality burr grinder.
Many people new to grinding their coffee fresh make the mistake of grinding their coffee too fine in the mistaken belief that grinding the coffee to a fine powder will release the most flavor. While that makes chemical sense — more surface area exposes more coffee oils to the water as it passes through the coffee grounds — it doesn’t necessarily hold true across all types of coffee brewing. In fact, if you grind the coffee too fine for the brewing method, you’ll end up with over-extracted, bitter-tasting coffee. On the other hand, if your coffee grounds are too coarse, the water won’t extract enough flavor components and your coffee will be weak and watery. In general, the longer the coffee will be in contact with hot water, the coarser the grind should be.
Cold Brew Coffee or Toddy Coffee: very coarse grind, about the texture of potting soil
French Press, Vacuum coffee maker or percolator: coarse grind, with distinct granules, about the size of freeze-dried Folgers crystals
Mr. Coffee style drip coffee makers with flat bottom basket: medium grind with coffee grains about the size of coarse sand or corn meal
Melitta style drip coffee makers with cone-shaped filter holders: medium/fine grind between coarse sand and granulated sugar
Stovetop espresso pots and smaller cone-shaped filter pots: fine grind of coffee, about the texture of sugar or salt
Espresso machine: Very fine grind, about the texture of superfine sugar
Turkish pot: Turkish grind, a very finely ground powder that’s similar in texture to white cake flour or powdered sugar