Sherlock Holmes had his Moriarty. Superman cowered in the face of Kryptonite. But for your coffee beans, no matter how powerful and robust they seem, the big enemies are air and moisture. Just a hint of exposure to these dastardly elements, and your coffee's precious oils (which are the source of all that yummy flavor) will disappear as fast as the Invisible Man. When you've spent hard-earned cash on expensive beans, how can you keep them as fresh as the day they were roasted?
The Whole (Bean) Truth
Step one to keeping your coffee beans fresh is to buy and store them in whole bean form. Once ground, more of the bean is exposed to air, and the process of deterioration begins. You may have noticed that your favorite gourmet coffee shop grinds each pot before brewing, despite the fact that pre-ground would be much quicker. Purveyors of the good stuff know that fresh ground coffee from whole beans tastes considerably fresher.
Trash That Bag
When you buy coffee by the pound, the store usually packages it in those little bags with the fold-over tops. While they may seem convenient, especially of you can't resist the temptation to buy a million kinds at once, they spell trouble for your coffee's freshness. However handy they seem, never store your coffee in the bags. The flimsy paper packaging exposes the beans to air, moisture, and even smells from your home. Think of them as temporary transport, like the baggie your goldfish comes in.
Seal the Deal
Even if you purchase your coffee in a metal can, the lid is far from airtight. You'll need to transfer the coffee to another jar. Choose a ceramic, glass, or heavy plastic container with an airtight lid. Look for one that has a rubber gasket closure, like the ones often used for flour and sugar. The main point is that it is able to be sealed and keeps air from contaminating those beans. Think of your container as the Fort Knox of coffee. Tip: Pour coffee from a metal canister without spills by making a hole in the plastic lid before transferring.
Even after reading all of the reasons why you should store coffee in a sealed container, there will still be some of you who still choose to keep it in the store bags. Whether it's because you go through it quickly, or just because you can't be bothered, your beans are in the cabinet in little, folded-over paper bags. If this is the case (and there's no changing your mind), do this at least: rubber band the top. While it's no substitute for airtight storage, using a band or clip on your bag will at least keep out some of the unwanted air.
Keep Cool...But Not Too Cool
Whether you've chosen to store your beans or grounds in a canister or the less-desirable bag, you'll want to make sure the container itself is in a cool, dry place. Depending on your kitchen, that may mean a cupboard or a counter top away from the heat of the stove. What it doesn't mean is the refrigerator. Even if your mother, your grandmother, and your grandmother's barista tell you it keeps better there, it's the worst possible place to store beans. Moisture and condensation from the fridge virtually attack the bean's aromatic oils. Besides, do you really want your special Kona to taste and smell like last week's Chinese takeout?
Ideally, you want to keep your coffee beans out of the refrigerator or freezer, but there is one situation when the freezer is your friend. While it's best to purchase small amounts of coffee at a time to ensure freshness, sometimes you'll encounter an irresistible sale and end up with several extra pounds of java. If you end up with more coffee than you can reasonably use in a short time, store the excess in freezer bags (make sure there is no extra air), and be sure to use them within a few months. Once the beans are out of the freezer, keep them out.
Following these tips should make sure that every cup of coffee you drink tastes from-the-roaster fresh. The real challenge is buying fresh beans from the start. Give your beans a good sniff at the store. Do they smell earthy? If yes, take them home and store them well. If they smell dull, then make the best choice you can possibly make for having fresh java: shop at a different store.