Coffee is roasted. Coffee has an initial “de-gassing” and then coffee is ready to consume. That's the basics in layman's terms.
Here are some thoughts I have been exploring:
Different coffees are ready after a different amount of days, and furthermore, different coffees (in terms of realized flavor extraction) age differently. That being the case, it would make sense to construct your espresso blends to reflect this. So if you have a Sumatran coffee that takes 5 days to degas and a Guatemalan that takes 2 days, and an Ethiopian that takes 1 day, then if you roasted the Sumatra on Sunday, you would roast the Guatemala on Wednesday, and the Ethiopia on Thursday. By doing this, all the coffees are “ready” at the same time.
The second factor would be the longevity of said coffees flavor nuances. Now we know about coffee being good for X days from roasting, but in terms of realized flavor extraction of various beans at different roast profiles there is a window of useability for espresso that may or may not correlate with the specifics we find for brewed coffee. Yes, it may be a plus or minus shift of a day or two, so it is worth considering.
This is not detailed by any means, but it's something to get you to think a little bit. As a practice, it's certainly not a a simplistic one. You need to consider other factors, like: Does the flavor intensify over the useable time, and then drop off like a Dry Processed Ethiopian or does it peak from days 6-10 like a Central American coffee? What about percentages in a blend? How does roast level affect flavor nuance and stability? Then you correlate those factors to the initial degassing time and come up with a new set of variables. This is a simplistic look at some of the little discussed factors involved with maximizing the flavor potential in your espresso, and it is something I would suggest thinking about if you want to improve your craft.
If you think about these kinds of things when you are roasting and blending, and would like to have a discussion, share your thoughts with me @ caffedbolla AT Yahoo DOT com.