In our first installment on coffee freshness, we discussed internal components that roasted coffee beans release. This time we will be focusing in the opposite direction—it is also important to know about the external stimuli that can contribute to the staleness of roasted coffee.

The big ones are light, oxygen, temperature, and moisture.

The reason why anyone in the know will tell you to keep your coffee in a dark place is a process called photodegradation. Photons in any kind of light can break down organic compounds in the roasted coffee beans like pigments, fats, proteins, and vitamins. Too much exposure to light will make your coffee lose its flavor.

Exposure to oxygen is also something that you want to avoid. Oxygen molecules are highly reactive, when they come into contact with other molecules they remove an electron, making the unfortunate other molecule unstable. In coffee this affects organic flavor compounds: fats and oils.

Most people are aware in some form or another that keeping foodstuffs at cooler temperatures helps them last longer. This is why we all have refrigerators and freezers in our homes. Keeping your coffee in a cool place is definitely preferable to a hot one—cooler temperatures slow down the chemical processes the make the coffee beans lose their flavor and aroma. The twist here is that putting your coffee in an artificially cold environment, like the fridge or the freezer, and taking it back out into room temperature to brew, can create another of roasted coffee’s enemies: moisture.

When roasted coffee comes into contact with moisture, it picks up water which accelerates the loss of flavor and aroma compounds. Worst case, too much moisture can make roasted coffee beans go moldy. You really don’t want to get your coffee wet. This is the problem with storing coffee in the fridge—taking it in and out every day causes moisture to form, spoiling your beans. If you want to preserve your coffee for an extended time you can freeze it in an air-tight container. However, you should only take it out and defrost it once—that means either storing it in portion sizes or keeping it in an unopened bag until you are ready to use that whole bag.

Luckily for all you Raven’s Brew Coffee® fans out there, our packaging is already optimized to keep your coffee in its best condition.

The high-barrier poly-foil blend keeps out oxygen, light and moisture, and the one-way valve allows the freshly roasted beans to release CO₂ without oxygen getting in. We even make our 12oz bags resealable with the included tin-tie. If you want to use your own container, use something that does the same tasks as the bags—blocking oxygen, light, and moisture. Raven’s Brew® offers Airscape® canisters that work great! And always remember, keeping your coffee in a cool, dry, dark place—whatever you store it in—is the single best thing you can do to extend its flavorful life!