How does the coffee machine work

How an espresso machine works
The principle of the espresso machine is to use a mixture of high-pressure steam and water to quickly pass through the coffee layer, instantly extract coffee, so that the coffee temperature is very high, the content of caffeine and other impurities is very low, and the taste is rich. At first, it was a semi-automatic coffee machine, we are used to calling it an Italian coffee machine, because it originated in Italy and got its name, and today, the Italian coffee machine has also been fully automated. The machine initially grinds powder, presses powder, fills powder, brews, and manually removes residue.
The principle of the American coffee machine is to dissolve, the hot water drops to the coffee powder, the coffee is dissolved in the hot water, and the coffee is filtered. Espresso machines are a bit like high performance liquid chromatography. The coffee is extracted by running hot water through the ground coffee at about 9 atmospheres of pressure. The difference with the American coffee machine includes: the coffee powder is filled into a cylinder shape, and the hot water is pushed through the coffee powder at a relatively high pressure, which can extract the oil inside the coffee.