When coffee is fresh roasted, it releases CO2 gases. When the coffee has aged (about 4 weeks), the gases are almost minimum. The gases escaping from the bean isn't the issue, its the flavors and aromas that leave with the gas that is the problem. In other words, the way that fresh roasted coffee she tasted on today, will not taste the same in 2 or 3 weeks. If the coffee is ground, this accelerates the aging process. Also, coffee is very porous and absorbent. So if she places her coffee next to her dried herbs and spices in the cabinet, it is a good chance her coffee could end up taste like rosemary for example.
Canned coffee from the grocery store is usually old when purchased. On average, coffee purchased from your local grocery store is about 3 months old. Even the most sophisticated packaging cannot stop the aging process.
Please see image below. I took 2 equally size samples of coffee and put both samples into a Melitta. I poured equal amounts of hot water from a kettle onto both samples. On the left, is our coffee that was roasted 2 days ago and on the right is a canned coffee I purchased from a local grocery. As you can see, the coffee on the left is very fresh by the amount of foam or bloat that is on top. That "bloom" as some call it, is caused by the gas that is still trapped in the coffee. The sample on the right has no bloom and is flat because its age. The bulk of the flavor and aroma is already gone on the. The opposite is true on the left and so those flavors and aromas will end up in the brewed cup of coffee.
This why I reccomend drinking that fresh roasted coffee when it is first purchased. It just dies. I wish I could say BeanFruit's coffee won't ever get to that point, but it eventually does if it isn't consumed soon enough. That's why roast it and sell it witihin 2 weeks of roast date. That makes sure the customer gets the full enjoyment of the coffee. Its a beautiful thing. What does your coffee look like? Give it the test and see. Be blessed.