How to make a good espresso and what's the difference between the American way?

How to make a good espresso and what's the difference between the American way?

The higher the brewing water temperature, the less sour coffee, bitter and burnt, the lower the water temperature, the higher the acidity, bitter and burnt, so the ideal water temperature should be adjusted according to different beans and recipes, such as deep roasting with lower water temperature, light roasting with higher water temperature. My favorite water temperature is 91 degrees.

Most household machines are difficult to stabilize due to the use of heating blocks or smaller boiler water temperatures. In the process of extraction, the temperature difference can reach 10 degrees, even if the operator is careful, it cannot overcome this hardware bottleneck. Large mainstream commercial machines (heat exchange type) also have a temperature difference of 4-8 degrees, so there are considerable requirements for operator control. Double-boiler and multi-boiler systems have independent PID temperature control coffee machines, temperature control is relatively easy to achieve stability, I use Aibo double boiler can make a cup of esp extraction process only 0.5 degrees temperature difference, higher-end coffee machines such as synesso, slayer, etc., can control the temperature in the range of 0.1 degrees, and the human taste for temperature influence resolution limit is about 0.3 degrees, So 0.1 degrees of temperature control is perfect for humans. In the coffee machine hardware we often say, the most commonly mentioned is the boiler size and pump (pump). In fact, there are many coffee machines to pay attention to, and the design of different pipes of materials will affect the effect of a cup of coffee. First, copper has good thermal conductivity (to ensure uniform temperature stability) and ductility, even in the frequent alternation of cold and hot metal fatigue is not easy to occur. Stainless steel is more hygienic and durable. Because stainless steel appeared relatively late, many manufacturers still use traditional copper to make coffee machines. Plastic, aluminum, these materials are completely unreliable, household machines are commonly used, relatively cheap.

Getting the perfect espresso may take more effort than you think, but you end up with more fun and delicious coffee.

The extraction of esp has a higher pressure, so use a fine enough powder. Under the premise of fine as much as possible uniform, so that the coffee powder under the pressure of uniform extraction. This requires a bean grinder that can perform well. Italian grinding machine is mainly divided into two kinds of cutter head-parallel cutter head and conical cutter head, the advantage of parallel cutter head is to ensure the uniformity of grinding. The powder ground by the conical cutter is composed of particles of different sizes. Since the coffee powder is uniform, why use the conical cutter? Because the cone mill uses a low-speed high-torque motor, the grinding is fast and not easy to generate heat, so the advantage of the cone mill is obvious when grinding a large amount of coffee powder. In addition, some people think that although the cone knife grinding is uneven, it can lead to more layers of flavor, and some people also say that uneven is easy to lead to miscellaneous flavor, so the cone knife itself is a controversial type, different opinions.