For those who enjoy a delicious cup of coffee in the morning, popping open a can of instant Folgers or putting a Keurig coffee pod into the machine may be just fine, thank you. For those individuals who appreciate a well-crafted cup of coffee made with freshly ground beans, you'll want to go with a quality coffee grinder.
Coffee beans are similar to eggs where as long as the outer shell is intact all of the goodness is sealed inside. Once that shell is compromised, the stuff we want inside becomes tainted and begins to deteriorate. I doubt you'd eat an egg that was cracked open and sat around in a tin can for a few weeks. Well, this is Everything2, so perhaps there are a few who would.
Rather than get a bag or tin of pre-ground coffee that has been on a shelf for weeks, or even buying beans at the store and using their grinder, you will get the most out of your cup of coffee by grinding only what you need immediately before brewing.
Locked inside each bean are aromas, flavors, carbon dioxide, natural chemicals, and oils. All of these will begin to deteriorate as soon as the bean shell is broken. The aromas and flavors are water soluble, which means they'll immediately begin to dissipate due to moisture in the atmosphere. The carbon dioxide will also begin to dissipate into the atmosphere, and CO2 is essential to help release the oils. The oils begin to oxidize immediately.
Think about it this way -- once you open a tin of cheap Great Value (Wal-Mart) coffee, it smells good. When you're down to half of a can, that fresh coffee smell is mostly gone.
Match the Grind to the Method
Different brewing methods require different amounts of grinding. My personal favorite methods are French press and a Galileo or Vacuum brewer. Both require a different amount of grinding to extract the most out of the beans. The more the beans are ground, the less time is required to get the good stuff out because there is more surface area for the hot water to work with.
Overall, here are some of the grind levels matched to the brewing method.
- French press
- Coffee percolator (Grandma's electric or stovetop)
Note: If you use paper filters in your drip coffee machine, use the brown filters, not the white ones. They are similar except the brown filters are not treated with bleach, which can leech into your coffee. Since most pre-ground coffee comes in a medium grind because the drip method is the most popular, it won't work as well with other brewing methods. You will get coffee, but it's not optimal.
Tell Me More About the Grinds
- Coarse: You can see larger chunks of beans. I like my coarse grind for my French press to have each bean chopped into 30-40 pieces. It tends to be pretty granular, more chunky than the stuff you buy in pre-ground tins at the store.
- Medium: This is what you're used to if you buy tins of pre-ground coffee.
- Medium-Fine: This is finer than you're used to, more like grains of sand.
- Fine: At this point you approaching a powder or flour consistency, but not quite there yet.
If you use a finer grind than expected, you will end up with more coffee grinds in your coffee cup. For example, if you use a medium-grind in your French press, the granules are smaller than the metal screen and can pass through. This is another reason not to let the screen of your French press contact the coffee layer or crema, the foamy layer on the top, to allow the coffee grounds to expand as they absorb the hot water.
Automatic or Manual?
Like a car transmission, whichever grinds your gears. I find both work well, but I prefer an automatic with a timer to get a consistent level of grind. Those tend to be more expensive, so if you don't mind turning an old-fashioned crank as a morning workout, that works too. I also find the automatics work better for the finer levels, but if you're going for the coarser brewing methods you can keep Grandma's grinder working in your kitchen.
re coffee grinder: There's a noticeable difference in consistency between grinders that cut the beans with whirring blades (less uniform grind), versus grinders that chip away at them using burred bits or gears (very uniform grind).