Mameshiba: Japanese bean-dogs who appear randomly and offer unrequested bits of triva

Storage is a complicated subject. This is a quick overview, and there are some specific circumstances that will be neglected. We'll pick those up later or in response to comments

Once you have your coffee beans at home, the best indicator of freshness is aroma (at room temperature) and taste. A visual indicator is the amount of "bloom" when you pour the water over the coffee. Coffee roasting creates significant amounts of carbon dioxide within the bean. Grinding releases the CO2, which carries the aroma into the room. (Smells great, doesn't it?) The remaining gas will be liberated as foam during brewing. Generally, the more bloom there is, the fresher the beans. (Geek note: the volume of CO2 varies among varieties. The range is three to 20 times the bean volume.)
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