I am getting conflicting information online about whether or not coffee needs to be stored in an air-tight container. There seem to be two camps:
- Container must be air-tight
- Container must have CO2 vent
Even coffee canister manufacturers seem to be at odds with one another. Take the following two products for example, both of which I own. The first is air-tight with a strong vacuum seal whereas the second has an opening in the lid that takes the same type of CO2 filter you see in commercial coffee bags (in fact, I will tear them out of the bags and use them with this canister as they're usually the same type as the ones that initially ship along with it).
So what is the final answer as to the proper way to store coffee, specifically whole beans in this case? What are the implications of CO2 build-up in the canister if you open the canister several times per day? Is the CO2 filter on a home coffee canister just a gimmick that only serves a purpose on coffee bags that sit on a shelf sealed for days or weeks on end?