How to do Espresso full-bit parsing well

Machine-stable brewing water temperature

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-boiler and multi-boiler systems, it is easier to stabilize the temperature. With expobar's double-boiler machine, the temperature difference in the extraction process of a cup of esp is 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 to the effect of temperature is about 0.3C. So 0.1 degree temperature control is perfect for human beings.

Machine-- an overall good heat conduction material

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. Plastics, aluminum and other materials are mostly used in household machines for the purpose of cost saving.

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Grinding-coffee powder that is fine and uniform enough

The extraction of esp has high pressure, so it is necessary to use enough fine powder. In the fine premise as far as possible uniform, so that the coffee pressed powder under the same pressure to get uniform extraction. This requires a bean grinder with good performance. The Italian bean grinder is mainly divided into two kinds of cutter head-parallel cutter head and conical cutter head. The advantage of parallel cutter head is that it can ensure the uniformity of grinding. The powder produced by the tapered cutter head is composed of particles of different sizes, since the coffee powder is uniform, why use the conical cutter head? Because the cone knife grinding uses a low-speed high-torque motor, the grinding is fast and not easy to heat, so the advantage of the cone knife is more obvious when grinding a large number of coffee powder. In addition, some people think that although the cone knife grinding powder is not uniform, it can lead to more levels of flavor, while others say that uneven is easy to lead to miscellaneous smell, so the cone knife itself is a more controversial type, different opinions.