How to use the grinder to help coffee extraction uniformity, fines, calorific value, static electricity

How to use a grinder to help with coffee extraction

uniformity

Coarse coffee particles are more likely to be under-extracted, while finer particles will be over-extracted in advance, so the larger the coffee powder, the more turbid and irritating the taste. However, when coffee powder with the same grinding particle size and relatively similar shape is extracted, the taste becomes brighter and stronger, and the performance of flavor characteristics is clearer and more consistent.

fine powder

Coffee powder close to flour can easily be over-extracted and even dissolved in water, thus affecting the extraction taste of coffee. The more fines, the easier it is to over-extract coffee and the more bitter it tastes. When making espresso coffee, the fine powder is first washed out by the water flow into the cup. If extracted properly, the dense oil will lift the fine powder, and the fine powder will float on the surface of the oil to form a beautiful "tiger spot". But "tiger spot" doesn't represent how espresso tastes. The production of fine powder can be reduced by selecting a better bean grinder or using a screen. But if there is no fine powder at all, the brewed coffee will also lack a sense of hierarchy.

calorific value

The grinding disc of any bean grinder generates heat during the grinding process, and the coffee powder is heated to accelerate the oxidation process, accelerate the aroma volatilization, and cause the brewed coffee flavor to be weakened. The calorific value of the cutter head depends on many factors such as the size of the grinding disc, the material, the structure of the cutter, the fineness of the grinding, the speed of the motor, the hardness of the coffee beans and so on.

electrostatic

In general, the finer the grinding, the faster the grinding machine, the stronger the static electricity generated; the internal material is plastic, the lower powder mouth does not use the static electricity reduction design of the grinding machine, the static electricity generated is stronger; the fat rich, roasting degree of coffee beans for grinding, the static electricity generated is stronger. Italian bean mill in the grinding often appear fine powder into a group, affecting the density of the powder after the cloth, resulting in uneven extraction; and single bean mill powder outlet magnet is through electrostatic adsorption silver skin and fine powder, to help reduce excessive extraction taste and miscellaneous taste.