As you lean against the counter and enjoy your first sip, you glance over and see the two pounds of coffee that you just bought and that's when you wonder how to store coffee fresh in such a way that it will not lose its flavour. Even though it was on sale, it did cost you plenty and the whole point of buying that much was to enjoy it for weeks to come.
So what to do? What's the best way for storing coffee?
The ideal way to obtain the freshest possible coffee is to buy unroasted beans, then roasting and grinding the beans on the same day you plan to brew. Freshly roasted beans naturally release small amounts of carbon dioxide which helps to keep oxygen away from the bean, delaying spoilage. If stored in an airtight container, especially with a drying agent, they'll retain their good flavor and aroma for up to a week. Beans, even after roasting, will stay fresh for a while. The closer to roasting, beans are ground and consumed the fresher they'll be. But even after a few days they can still produce a stellar grind and a superior brew since freshly roasted beans naturally release small amounts of carbon dioxide which helps to keep oxygen away from the bean, delaying spoilage. The flavour may still be acceptable after two weeks, even though the aroma will no longer be first rate. Whole bean coffee stored at even optimum conditions will be dull after a month. Key to getting a good cup from purchased roasted beans is to ensure that the skin is unbroken. When that happens, all bets are off. Oils underneath the skin and inside the bean will deteriorate unless frozen, in which case the brew will never be first rate.
When storing coffee beans, be sure to use an airtight container. Best are containers which flush air with an inert gas, then inject the coffee beans which then give off CO2, providing natural protection against spoilage. Beans stored in this way can keep their freshness for several weeks. A good glass jar with a rubber seal is another option. Be sure to store the jar in a cool, dark place since not only air, but also light and heat can contribute to spoiling beans.
The next best thing to home roasting, and an option open even to those with less than stellar cooking skills is grinding at home. Since grinding necessarily breaks the bean skin the same 'oil spoilage' problem can arise if the grind isn't used within a few days. Like roasted beans, only more so, any grounds not consumed within a day should be packed in a desiccating cannister. Those cannisters contain a drying agent, usually beneath a mesh at the bottom, that keep moisture from introducing mold or excess oxygen into the grounds. If not stored in a desiccating cannister, grounds will lose much flavour within a few hours. Oils will evaporate and, exposed to the air and moisture within the jar, the grounds will deteriorate. For a superior cup, grind only what you intend to brew and drink everything brewed within an hour. With modern, moderate cost machines there's no longer any reason to suffer second-rate coffee.