How to grind coffee beans? what is the grinding degree of coffee beans? what's the knack for choosing a bean grinder?

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[preface]

In the previous articles, I told you how to choose the right hand-flushing equipment and coffee beans. Today, I will tell you how fine the coffee beans should be ground. The roughness of grinding not only affects the extraction rate of these substances, but also greatly affects the flavor of coffee.

The finer the grinding, the coffee powder is easy to accumulate on the filter paper, and the extraction resistance is greater, so the flow rate is slower and the extraction time is longer. The extraction rate of the substances contained in coffee is high, and the coffee brewed is stronger; the thicker the grinding is, the larger the gap in the powder layer is, the less coffee powder is in contact with hot water, the weaker extraction resistance, the faster coffee dripping speed and the lower extraction rate, so the flavor of coffee is lighter.

The thickness of coffee powder is related to the amount and speed of coffee ingredients released when brewing coffee. Generally speaking, the thickness of coffee powder can be divided into five grades: very fine powder, fine powder, medium powder, coarse powder.

(1) very fine powder: suitable for espresso

This is the best to understand, and the usage is relatively absolute, only used when making espresso. Because the extraction method is different from the usual principle of brewing at home, it needs to be pressurized, so the appliance is an Italian coffee machine, and the grinding also requires a professional coffee mill to achieve extremely fine.

Because when making espresso, we must make efforts to fill the coffee powder to make it resistant to high-pressure hot water, so that we can really extract the essence of coffee. Therefore, it is more sensitive to the degree of grinding, the more uniform grinding, the more compact the coffee powder, and less space, can produce balanced resistance to water, so that a cup of Espresso can be extracted successfully.

If you use a mocha pot to make coffee, it is also more suitable to use very fine powder, but the extraction is generally excessive, although a little oil can come out, but the taste is bitter, and the enjoyment process is often greater than the taste itself. At the same time, we should not blindly pursue grease and grind the beans too fine, otherwise it will plug the exhaust hole and cause danger.

(2) Fine powder: suitable for hanging ears

Fine powder is suitable for hanging-ear coffee. Many people will think that some of the ears should be soaked in water, and thicker particles should be used. In fact, it is mainly because the ears are all filter paper, and the water output is very large. Unlike hand flushing with a closing position, such as the commonly used three-hole filter cup, it actually slows down the speed of water outflow, so hanging ears need fine powder to increase the extraction area and extract more substances.

(3) medium and fine powder, (suitable for light baked beans, small Fuji ghost teeth 3.5)

Medium and fine powder ≈ white granulated sugar (the most common white granulated sugar in the supermarket, a little bigger than that). Generally, the hand will eventually be fixed on the thickness of the medium and fine powder, because the medium and fine powder is very commonly used, so if you love coffee, you should try your own coffee mill and find the most suitable level of medium and fine powder.

(4) medium flour (suitable for medium-baked beans, small Fuji ghost teeth 4)

Medium powder = granulated sugar (the largest granulated white granulated sugar seen in the supermarket is this kind of thickness most of the time), the medium powder is slightly thicker than the medium fine powder, but not as large as the coarse powder.

It is recommended that beginners first use coffee bean powder for hand flushing, after all, the grinding powder is not easy to produce very fine powder, nor is it easy to soak coffee powder in the filter cup due to the accumulation of water in the filter cup at the beginning of the unstable flow control, thus causing coffee extraction to be excessive. In addition, because personal tastes are different, you can try more between medium powder and fine powder to find a suitable thickness.

(5) coarse flour (suitable for medium and deep baked beans, small Fuji ghost teeth 4. 5)

Coarse powder (with coarse white granulated sugar, finer than yellow sugar,), suitable for siphon pot and pressure, coarse powder in high water temperature extraction, it is not easy to extract bitter taste, the same can not be ground too coarse, the taste will be light if the extraction is insufficient.

A more uniform degree of grinding is also important:

Coffee beans become powdered after grinding, and the distribution of powder size has a lot to do with the quality of coffee drinks. If there is too much fine powder of coffee powder and too much contact between water and the surface of coffee powder, the fine powder will give priority to extract too many unnecessary impurities, even bitterness; while the relatively coarse powder particles, the taste is not extracted, where there is no contact with hot water, the brewed coffee does not have enough aroma. Half of the extraction is insufficient, the other is over-extracted, and the taste is certainly not very good.

However, an appropriate amount of uneven grinding will bring a sense of hierarchy, so it is necessary to control the extraction time. When we use the V60 filter cup, the thickness of the powder layer is larger, and the contact time between the powder and water is longer, usually the fine powder is easy to gather at the bottom, and it is easy to extract bitterness from soaking for a long time, so it is necessary to control the amount of fine powder. If the home grinding the same scale of fine powder is too much, you can use a powder sieve to keep the fine powder in a certain range.