Why is the basic coffee of fine coffee brewed?

Many young friends, including some old people, of course. They are very strange to coffee, and whenever they talk about making coffee, they find it very difficult to understand, thinking that it is a very skilled and complex activity. The Chinese tend to generalize the production of freshly ground coffee with the word "boil". Well, for these friends, I will try my best to introduce this question to you.

First, why should coffee be "brewed"

If you know a little bit about coffee, you must know that coffee is roasted by raw beans at high temperature into the brown beans that we are all familiar with. So why can't coffee just like tea, pour these beans into a pot and boil them, or soak them for a while to make a cup of strong coffee?

We know that coffee is different from tea, it is a seed. Its density is much higher than that of tea, so it can't be eaten directly. It needs to be baked at high temperature, which is actually puffing. Because only the lignocellulosic structure of extruded coffee beans can be opened. Aromatic substances remain in crispy roasted (expanded) coffee beans. Coffee beans become larger and denser, and this process is necessary, otherwise we will not be able to get the taste of coffee (how coffee flavor is formed during roasting, which is too complex to go into detail here).

After the coffee is roasted, it needs to be crushed. The purpose of crushing is to increase the contact area between hot water and coffee powder. This will cause more aromatic substances to be extracted. We call this phenomenon increasing the extraction rate. Therefore, the whole coffee beans can not be completely extracted from the taste of coffee, so the coffee beans can not be boiled directly.

The next step is to use water to extract the taste of coffee from the coffee powder, and Jiner also has the color of coffee. So we have to drink a cup of coffee, coffee beans need to go through: puffing-crushing-extraction, can be obtained. So coffee needs to be "brewed".