How to use the hand grinder of Yang Zi in Song of Joy what coffee machine does Starbucks use?

The hot water for brewing coffee is too hot, resulting in the loss of oil.

The steam boiler cannot provide enough pressure.

Even so, exerting extra pressure to shorten the time it takes to brew coffee is still worth the effort. Just don't use steam, what should be used as a source of pressure? The further question is: how much pressure does it take to get the best extraction rate?

A brief history of coffee machine development Ⅱ

Desiderio Pavoni obtained a design patent for Bezzera in 1903, and he has been making the coffee machine since 1905. After that, Teresio Arduino began to produce similar coffee machines, and other producers followed suit. In the 1920s, coffee shops in Italy could see signs of this kind of coffee machine. But the Italians are obviously not satisfied with the results of the steam pressure coffee machine. The pressure should be increased by steam, but increasing the heat may burn the coffee powder during cooking, losing the aromatic oil hidden in the coffee powder and making it more refined.

Take out the doubly bitter coffee. Therefore, some people think: can it be directly pressurized on the hot water instead of boiling the water with steam as the pressure?

During the two world wars, people used the natural pressure of water from the faucet to increase the pressure of brewing coffee. The coffee machine uses electricity to quickly heat a small pot of water to the boiling temperature, each pot of water to make a cup of coffee, each pot connected to the faucet. As long as the operator gently press the pole on the small pot, the pressure of the faucet will push the hot water in the small pot to the coffee powder. According to the difference of water pressure in different regions, generally speaking, the pressure generated by this coffee machine is greater than the 1.5 atmospheric pressure produced by the steam pressure coffee machine. The height of this coffee machine is not too different from that of the steam pressure coffee machine, but the overall size is smaller. The appearance is more in line with the popular trend of the late 1920s and 1930s, replacing the arc of the steam pressure coffee machine with straight lines and geometric lines.

Another way to generate more pressure than 1.5 atmospheres is to use compressed air. For example, a home coffee machine in Milanes collector Ambrogio Fumagalli uses an air pump to pressurize hot water for brewing coffee (during World War II). In 1938, Francesco IIIy made the llletta' Coffee Machine, a large commercial coffee machine based on the principle of compressed air. When the crossbar on the coffee machine was lifted before World War II, water was injected into the space occupied by the piston and pressed down, and the pressure on the piston injected water evenly into the coffee powder in the filter. this means that hot water can brew coffee before it boils without scalding the coffee powder. At the same time, Achille Gaggia, the owner of a cafe in Milan, used a similar method to brew coffee. This method is gradually adopted by other coffee machine manufacturers, so this new coffee machine is also gradually replacing the steam pressure coffee machine. Today, the application of this principle can still be seen on household machines-La Pavoni.