The difference between flat knife and ghost tooth bean grinder-domestic small Fuji ghost tooth bean mill

The difference between flat knife and ghost tooth bean grinder-domestic small Fuji ghost tooth bean mill

Among the factors that determine the taste of coffee brewing, "beans", "grinding" and "machine" are hardware factors, and "technology" is software factors. Many people are struggling with bean grinders, conical knives, flat knives, ghost teeth, and which of the three different types of knives is better?

Bean grinders can be divided into three categories: flat knife, conical knife and ghost teeth.

Flat knife: coffee beans are ground into particles by cutting, so its shape is mainly flaky.

Cone knife: the coffee bean is ground into particles by grinding, so its shape is mainly block.

Ghost teeth: coffee beans are ground into particles in the way of grinding, so their shape is mainly close to circle.

Many choices of bean grinder are very tangled, we often make coffee data to find good coffee, but there is no suitable bean grinder, coffee flavor did not spread out, no matter how good beans are a waste! In particular, the screw-type bean chopper (we call it the bean chopper because this machine crushes beans by chopping rather than grinding) not only can not process coffee beans into uniform coffee powder, but also generates a lot of heat in the process of chopping. Coffee powder accelerates the oxidation process when heated. The flavor will also be taken away!

Under the first principle of successful extraction of fine coffee (uniform extraction), because the coffee powder particles chopped by the chopping machine are coarse and fine, it will also lead to the failure of coffee extraction! The most direct is excessive extraction, or insufficient extraction! The coffee with insufficient extraction will be sour and astringent, and the coffee with excessive extraction will be too bitter!

1. 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.

When you need to get a high concentration of coffee in a short time, the flat knife grinder is a good choice, and the high concentration will also make the aroma rich, so the aroma of the flat knife will be much more obvious than that of the cone knife; when a better taste is needed, the granular coffee powder produced by the cone knife can reduce the time for xylem to come into contact with moisture, although the aroma is not as obvious as the flat knife, but even if the extraction time is prolonged, the taste is still better.

Home magic bean machine recommended: 500-600 Pegasus in Taiwan, 300-400 in Taiwan

The ghost tooth grinding plate can grind more uniform coffee powder, produce less fine powder at the same time, and has higher grinding efficiency. 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.

Grinding comparison:

It is a common way to adjust to the same scale, such as scale 4, grind the same beans, and then observe the uniformity and powder thickness with the naked eye, but the cutter head design is different, the powder state under the same scale may not be the same.

Grinding effect diagram of positive sloshing flat knife bean grinder

Grinding effect picture of Xiaofei Eagle's round knife

Fuji Royal Rmur220 Japanese Royal Fuji Ghost Tooth Grinder

So what is the effect of powder structure on extraction?

Flat knife grinding flake particles will be closer to the oblate rectangle, while cone knife grinding block is close to hexagonal, ghost tooth grinding powder waist slender, relatively smooth, the coupling between powder and powder will be better.

The powder grinded by the knife is less than the raised fulcrum of the cone knife, the particles are lumpy, and the waist is stronger than the ghost teeth. A person thinks that the water resistance of flat knife powder should be the greatest!

Cone knife powder under the microscope, the main body of the powder structure will have many protruding outer fulcrum, just like a hedgehog. After many powder particles gather, it is impossible for the powder particles to match completely because of the external fulcrum. The gap will be larger and the flow of water will pass faster. The flow of water passes faster, so the extraction is relatively low.

Ghost tooth powder, ghost tooth grinding out of the powder waist slender, relatively smooth, the coupling between powder and powder will be better. The gap is also small, the flow of water through will be relatively slow, and the extraction will be relatively more. Ghost tooth powder waist is too thin, peace knife powder compared to the resistance must be less. Then the powder ground by the flat knife, from the structural point of view, the convex fulcrum of the powder particles is less, so the coupling is much better than the cone knife powder. The gap is tighter than the cone knife, the water resistance is also larger, and the extraction is also a little more.

In terms of taste, the same beans, the same amount of powder, the same water temperature, the same fineness of powder, flavor comparison:

The flavor of flat Dao is unrestrained and unitary.

The flavor of conical knife is more round and complex.

The flavor of ghost teeth is clean, and the flavor is three-dimensional and full.

Summary:

From the grinding point of view, is the more uniform, the less fine powder is better? This is not the case. As mentioned just now, each kind of knife head has its own advantages and disadvantages. If it is absolutely uniform and there is no fine powder at all, the taste of coffee will be very mediocre, lack of taste and hierarchy, and it is very easy to extract too much. If too much non-uniform fine powder will produce too much miscellaneous smell and affect the smoothness of the extraction, the taste and smoothness will also be greatly reduced.

If you really want to know which one is most suitable for your needs, that's why players and contestants buy so many bean grinders, ah, you can only know by comparing them, and there are experienced baristas who adjust the time and method of brewing coffee. And the degree of grinding to control the flavor of coffee, this will still not make the coffee perfect, so even world-class baristas are constantly pursuing high-end equipment. Constantly improve their own techniques.

When you need to get a high concentration of coffee in a short time, the flat knife grinder is a good choice, and the high concentration will also make the aroma rich, so the aroma of using a flat knife will be much more obvious than that of a cone knife.

When better taste is needed, the granular coffee powder produced by the cone knife can reduce the xylem contact time, although the aroma is not as obvious as the flat knife, but even if the extraction time is prolonged, the taste is still better.

When the overall taste is three-dimensional and full, choose the ghost tooth grinding plate to taste better.