How much pressure does it take to make a good coffee-espresso machine?

How much pressure does the coffee taste good?-how much pressure is the espresso machine?

In the coffee machine hardware that we often talk about, the most common mention is the size of the boiler and the pump (pump). In fact, there are many other things to pay attention to in the coffee machine. The design of different pipes of the material will affect the effect of a cup of coffee. This is also why responsible manufacturers use copper or stainless steel as the main material of the coffee machine. First, copper has good thermal conductivity (to ensure uniform and stable temperature) and ductility, and metal fatigue is not easy to occur even in frequent alternation of cold and heat. Stainless steel is more hygienic and durable. Because stainless steel appeared relatively late, many manufacturers still use traditional copper to make coffee machines. Materials such as plastic and aluminum are completely unreliable, but household machines are commonly used and cheaper.

The more factors we control, the more likely we are to get a good cup of coffee.

Although it is possible to judge whether to continue or stop the extraction according to the state of coffee outflow, breaking through the theoretical framework requires sufficient brewing experience, and it is more practical to give yourself a stable framework at the beginning.

More widely used amount of extraction

Single espresso 25-30 seconds extraction of 25-35ml Coffee

Double espresso 25 seconds-30 seconds extraction of 45-55ml Coffee

The higher the brewing water temperature, the lower the sour taste, the higher the bitter and scorched taste, the lower the water temperature, and the higher the acidity, the lower the bitter and scorched taste, so the ideal water temperature should be adjusted according to different beans and formulations, such as lower water temperature for deep baking and higher water temperature for shallow baking. My most commonly used water temperature is 91 degrees.

Water temperature control of most household machines due to the use of heating blocks or smaller boiler water temperature is difficult to stabilize, in the process of extraction, the temperature difference can be up to 10 degrees deviation, even if the operator is more careful, can not overcome this hardware bottleneck. And large-scale mainstream commercial machines (heat exchange type) also have a temperature difference of 4-8 degrees, so there are considerable requirements for the operator's control. For coffee machines with independent PID temperature control in double boilers and multi-boiler systems, it is relatively easy to stabilize the temperature. The Aibao twin boilers I use can make the temperature difference of a cup of esp extraction only 0.5 degrees Celsius. Higher-end coffee machines such as synesso, slayer, etc., can control the temperature within 0.1C, while the resolution limit of human taste for temperature effect is about 0.3C. So 0.1 degree temperature control is perfect for human beings.

The rotary pump is mainly used in commercial machines and high-end professional household machines because of its large size. The pressure can be stabilized within a fixed value, from a straight point of view, the pressure curve of the vibrating pump is fluctuating, while the pressure curve of the rotary pump tends to be a straight line, the two are not the same. The use of rotary pump is a major element of stable extraction. In addition, the noise of rotary pump is much lower than that of vibrating pump, and some vibrating pump noise makes people feel unsafe and cheap, and noise can also affect people's mood, so it is not recommended to use vibrating pump coffee machine as a business machine.

At present, the standard of esp brewing theory is 9 ±1 and 9 ±0.5,9 ±2 respectively. Here in order to facilitate the memory and understanding of the individual is set at 9.