Coffee grinder, hand grinder or electric grinder? What's the difference?

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Hand coffee grinder

As the name implies, it is a hand mill, and just turn the handle of the beans by hand. Isn't it easy to operate?

The old hand-grinded coffee machine cannot adjust the grinding degree of coffee powder, but with the changes of the times, the hand-grinding coffee machine can also adjust the grinding degree, generally at the top, there is a spring on top of a nut, which can be rotated. We can see that after rotation, the direction of spring compression is the fine direction and the opposite is the thick direction.

The new hand grinder will be convenient to carry and suitable for use when traveling. It is small and does not take up space.

Electric bean grinder

It is electric, convenient and fast, can adjust the degree of grinding and is more convenient. There are a lot of choices. But it generates a little bit of heat.

. The grinding standard is the same, but the flavor is different.

The core grinding plate of the bean grinder is mainly divided into cone grinding plate, flat grinding plate, ghost tooth grinding plate, which of the three different grinding plates is better? For the same beans, the taste of the coffee entrance is different when the grinding degree of the bean grinder with three different plates is basically the same. Although the main flavor is the same, but the details of the structure is very different! Why?

two。 The structure of powder particles determines the flavor

After grinding, the structure of powder particles is completely different, cone grinding plate, flat grinding plate, ghost tooth grinding plate. Through grinding, it can be observed that the powder structure and shape of different knife shapes are completely different. The effect of powder structure on the flavor of coffee is also related to whether the extraction is uniform or not, which has little to do with the extraction rate. Even if the extraction rate is the same, the flavor is still different, which is due to the uneven extraction.

Flat knife grinding plate

Advantages and disadvantages:

The flat knife bean grinder is composed of two upper and lower cutter heads, and the base is fixed on the motor. When the motor starts, it rotates the upper and lower cutter heads to produce cutting action.

When the coffee particles fall from the middle, the knife head rotating at the bottom will spin the coffee beans to the outside and push the coffee beans into the tooth cutter part for grinding.

The upper and lower cutters of the flat knife are placed in a parallel manner, so the coffee beans need to rely on the rotating force of the bottom cutterhead to push the coffee beans into the cutterhead, so the weight of the coffee beans placed on the top will affect the uniformity of the coffee beans entering the knife cutter. in addition, due to pushing, the number of collisions between coffee beans increases, resulting in an increase in the proportion of fine powder. This is the reason why the particle uniformity of the common flat knife bean grinder is slightly worse and the fine powder is more.

The coffee particles ground by flat knife are flaky, and the flake can increase the area of cell wall, so using flat knife can increase the concentration and extraction rate of coffee liquid in a short time, so that the aroma of coffee can be significantly improved in a short time. At the same time, because the shape is long and the volume is smaller, when the extraction time becomes longer, the granular xylem will absorb too much water, resulting in increased miscellaneous flavor and astringent taste.

Cone knife grinder

Advantages and disadvantages:

The conical knife grinder places a conical cutter head at the bottom, and then grinds it with the outer ring cutter head. After the coffee bean falls from above, it will pull the coffee bean down with the rotation of the conical cutter head, and then produce grinding action. Because of the relationship from top to bottom, the particles can push the coffee out without pushing. Compared with the peace knife grinder, the number of collisions between the particles will be reduced a lot. Therefore, the proportion of fine powder produced by the cone knife will be much less than that of the flat knife, and the uniformity of coffee grinding will be greatly improved.

The cone knife grinding particles will be nearly granular, resulting in a longer water absorption path of coffee particles, and it will take longer for the interior to come into contact with water, so the cone knife particles will release less soluble matter at the initial stage, resulting in a low concentration in a short period of time. At the same time, because the shape is granular, even if extracted for a longer time, the xylem absorbs less water and is less likely to produce miscellaneous and astringent taste.

Ghost tooth grinding plate

Advantages and disadvantages:

The coffee powder particles of ghost tooth grinding are close to round, and the proportion of coarse powder and fine powder is more uniform, so the coffee taste is cleaner, the flavor is more three-dimensional and full, but the machine price is higher.