Unlike green coffee storage, which can be a little more flexible when storing smaller amounts at home, roasted coffee storage is a slightly more delicate process.
Degassing. Firstly, once you complete a roast, your beans will need ample time to release the carbon dioxide they produced during the roast (“degassing”). We recommend that you wait a minimum 6 hours before brewing. If you’re patient enough, let your coffee rest until the next day (or as long as two or three days) for best results. During this period, it’s best not to seal your coffee in a ziplock bag or other container until the gas can dissipate.
After the resting/degassing period, your coffee should be stored someplace...
Airtight: Keeping your roasted coffee in an airtight container is critical to prevent staling. A plastic bag works, but it’s not ideal. Consider using a canister designed specifically for coffee, that locks out air and humidity. (This works for both green and roasted).
Temperate and Dark: Sunlight and unfriendly temperatures rapidly accelerate the staling of your beans. If your beans are in a plastic ziploc sitting on the window sill, they stand no chance. Tuck them in a canister and place them in a cabinet or cardboard box; something to prevent too much light from reaching them. Note also that a cooler environment is always better than a warmer one, as warm air contains more moisture (see below). This does not mean the refrigerator or freezer, though, where moisture and other food items can affect your beans.
Dry: Avoid any place that can get wet or is subject to humidity or moisture. Roasted (and unroasted) beans are hygroscopic and porous and will absorb moisture around them, accelerating flavor loss. Forget storing your beans next to your sink or dishwasher--put them in the kitchen cabinet in an airtight canister.
Freshness. Even if you follow the tips outlined above, you can’t totally keep your coffee fresh forever. Some roasters will say coffee should be drunk within a month, Red Can coffee never “goes bad”...per say…but for freshness, we recommend roasting enough coffee for a week or maybe two, and repeating the roast process more often to ensure you’re always drinking fresh coffee.
Staling. Same as the open bag of chips in your cupboard, coffee will stale. Proper storage helps delay the inevitable woody, cardboardey taste that you get when the coffee gets, well, stale. Note that lighter roasted coffee is less porous than darker roasted, and therefore somewhat less susceptible to moisture and other staling