The power of espresso powder How to press powder will extract balanced and delicious espresso coffee

The power of powder pressing (it may be easier than we thought)

The most basic question is how powerful it is and how much kg. I have heard of 25kg before, and I have also heard that Italians regard coffee as their life and touch it gently.

In explaining this problem, one of the most basic problems needs to be corrected. Strength should be described by Newton. It is not literal, the reason will be explained later.

If we explain it in terms of Newton, then let's convert it first. 15kg is a more commonly used description, so when converted into Newtonian units, it is 15kg*9.8N/KG, that is, about 150N.

Next, let's take a look at the power of nine atmospheric jets of water on Coffee pressed powder.

Nine atmospheric pressure means that in a unit square meter, there is a force equivalent to nine atmospheric pressure, which is 900KN/ M ^ 2.

The area of our average 58mm diameter pressed powder is (58 58mm 2 to 1000) ^ 2 to 3.14, that is, about 0.00264 square meters.

Then the pressure generated is 900, 000, 000, 0.00264, or 2380N.

The 150N produced by the powder hammer is obviously negligible compared with the flow of 2380N at nine atmospheric pressure.

At the same time, there is another important factor to consider. When La Marzocco designed the Swift automatic filling device around 2000, they experimented with forces ranging from 2 pounds to 30 pounds (that is, about 15kg). Found that no matter how much power, the power to the bottom of pressed powder is almost powerless. This is like a car collision experiment, where the extrusion and deformation of the car body itself is the result of absorbing energy.

Therefore, the conclusion drawn from these two points is very simple: the strength of the powder does not have much to do with it, as long as the powder is pressed tightly. At the same time, it is more important to keep the powder pressing force consistent every time.