Does freshly ground coffee taste good? what's the advantage of drinking your own coffee?

Everyone knows that freshly ground coffee is the best (that is, within the quality range of coffee beans). The question is whether this is true. Freshly ground coffee smells good, but does it affect the taste after brewing? How long will these volatile flavors or smells last before the coffee goes sour?

Fresh grinding: higher acidity and richest flavor.

9 hours: very similar to freshly ground coffee, but with slight changes. Reduce the "bright" notes.

24 hours: some fruit flavor disappears; it usually tastes less.

7 days: blunt, the overall flavor decreased significantly.

Flavor difference

Tastes will vary depending on specific coffee and brewing methods, but in general, fresh coffee is rich and tastes more like dark chocolate, while old coffee is boring and tastes more like dirt. From my experience, I can tell that it is difficult to learn.

In short, coffee begins to lose its freshness as soon as it is roasted. The longer it sits, the faster it becomes obsolete. The larger the surface area it has (that is, it has been ground; and the finer it is), the faster it will become obsolete. The more times you expose it to the air, the faster it becomes obsolete. Therefore, the coffee is sealed in a sealed container at room temperature. And grind as close as possible to the time of adding water.

When the coffee is ground (as long as it is fairly fresh), the coffee begins to oxidize and dissipate the gas scattered throughout the beans. The finer the grinding, the larger the surface area and the faster the occurrence. For espresso grinding, the window you need to use is about 30 seconds to one minute. When referring to "grocery store" coffee, it may have been in use for a year and lost most of these gases for a long time, so I am sure that the effect of grinding will not make a significant difference.