Once you realize that coffee has to be fresh and that it is a crop the next question is why must coffee be fresh and why can it be too fresh? Also what should you do if you cannot drink your coffee while it is at its peak? The oils in coffee that give it some of its great flavor are volatile. They break down over time like most oils, especially if exposed to air or to heat. Eventually they will go rancid. Like most foods the rest of the bean breaks down, too, over time. Coffee is a bit like wine in that as soon as it is exposed to air in some sense it starts to go down hill in taste. On the other hand also like wine there are some things that get better with time about the taste. Coffee off-gasses releasing carbon dioxide for the first week or so after it is roasted. Some people dislike this more than others. It can be compared with a faint taste of baking soda. For me personally most coffees taste their best from 7 to 14 days post roast, and this is what many roasters recommend for their beans, but others such as Chris Tacy who writes the worldclass blog called Godshot at:
finds coffee at its best earlier than that. I think the difference is probably about the flavor profile that one prefers. There are coffees, however, that I find are at their best after only a few days so it really does depend on the coffee. I have never found a coffee that was anywhere close to its best after three to four weeks. I also have never heard of an expert who thought coffee that old was at its best. There are, of course, coffees that are vacuum packed and gassed to “preserve freshness” for longer periods and some of these will taste good the day you open them, but they fall off in a matter of days, much faster than fresh coffee. That said there are ways to make your coffee last longer and we will talk about those soon.