Posted on June 03, 2010
I'd like to say a few words on a matter that there seems to be some confusion about. One of the more common questions I receive is "How should you store coffee?", or "Do you recommend freezing coffee?". The quick answer is yes, if you aren't going to consume the coffee within 2 weeks you should freeze it.
Given that the last post on our website was satirical in nature (see "Expresso Is King"), I'd like to clarify that this post is a serious one. Freezing coffee is a hotly debated subject in specialty coffee circles. A lot of people cringe at the idea of keeping coffee around for longer than a few weeks after roasting and I think because of this freezing is looked down upon.
What there isn't any debate about is the fact that coffee is a very perishable product. Virtually any coffee professional you could ask would agree that the ideal shelf life of roasted coffee at room temperature is a matter of weeks, if not days. At room temperature, I would suggest a 14-day window for espressos and a 21-day window for drip coffees. Bare in mind that these are guidelines, not rules. The older a coffee gets, the less flavor it has. That why freshness is key to enjoying the full potential of your coffee.
Coffee "staling" is a result of both chemical and physical processes. Over time, oxidation takes place which changes the many chemical compounds found in coffee that contribute to flavor. There are also physical processes taking place, such as CO2 "degassing". Probably just as important, coffee can absorb bad flavors from its environment.
There is a simple fact of chemistry that should be the end-all of this to-freeze-or-not-to-freeze debate. Chemical changes (reactions) slow down as temperature is decreased. There are a multitude of chemical changes taking place as coffee stales, and each happens at its own rate. But the lower the temperature, the slower these changes will take place.
There is still a right way and a wrong way to freeze coffee. If you don't freeze it right, you risk degrading the coffee even faster than simply storing it at room temperature. The real bad guy is condensation. Unfortunately, freezing introducing the opportunity for condensation to happen. Also, if your freezer has any odor at all, the coffee may absorb that. So give your freezer a good sniff before attempting this.
The key point here is don't take the coffee in-and-out of the freezer, because that will create condensation on the coffee beans which is very destructive.