Quickly learn the basic principles of hand-brewing coffee and explain the skills

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Principle of hand-brewing coffee

We still have to get back to the essence, extraction. This is not to say that the European and American hand rush is better than the Japanese style. In fact, the European and American hand Chong serves the operation to some extent. On the other hand, the Japanese-style hand flushing technique is more pleasing to the eye, and it is done well, and it is equally delicious, but the style is different.

There is a truth that we will understand that the thicker the powder, the less flavor will be extracted per unit time. Therefore, when you inject water, you will let the water stay for a long time. This explains why Japanese-style water injection places special emphasis on a slow and extremely stable column of water compared with Europe and the United States. And Europe and the United States, is a relatively fine grinding, you can use a faster flow rate, a short time to fully extract. (the Japanese style takes about three minutes to complete) therefore, it is relatively easier to master.

Secondly, there are two concepts of water temperature. First, the water temperature during the extraction of hand-brewed coffee and the water temperature during drinking. The reason why it is fixed at 94 °is also to improve the extraction efficiency. But I do not have a warm cup this time, I hope that the high temperature of 94 °will come into contact with the coffee powder, then flow into the pot, and then pour into the cup, there will be a gradual cooling. In this way, about 70 °in the mouth is a more drinkable "start".

The reason for putting quotation marks at the beginning is that it is different from espresso. Espresso only has 30ml, which will cool too fast. Cappuccino milk is affected by temperature and is delaminated quickly. So espresso cups tend to be preheated, and the walls are very thick for heat preservation. But filtered coffee such as hand brewing, from 70 °to 50 °, the taste of the coffee will change a lot as it cools. Although it can be simply summed up from bitterness to acidity, the acidity here is the process of fruit acid prominence. Therefore, filter coffee cups tend to be thinner and taste more "vivid".

There are two reasons why I let the last water run out (2 minutes-2 minutes 30 seconds). First of all, whether there is excessive extraction, mainly from the sensory experience. If there is a mixed smell behind, you can change the degree of grinding to adjust (see the previous extraction article), because excessive extraction is ultimately closely related to how much water is taken from coffee powder per unit time. If we move the filter cup directly every time we see the last water, we cannot accurately judge that the water content is the same each time. Second, if you change the amount of water at will, you will change many parameters, for example, the gram weight of coffee will be reduced, and the extract will be reduced (because less water will bring out the coffee substance), but not in proportion. Eventually your concentration will increase. But these variables make it difficult for us to find a suitable hand-brewing coffee rule.

If you find that the coffee is too sour, grind it fine, and if the coffee has a mixed smell after drinking it, what you can do is to thicken it. Of course, there is also a situation that is both mixed and sour. It depends on whether your extraction is uniform and the freshness of the coffee beans.

Let's go back to the process of hand-brewing coffee extraction, after all, the water is over-powdered and filtered.

Of course, I am not saying that you should fix other parameters and only adjust the degree of grinding. for beginners, it is easy to get started and you can find the feeling of different coffee.

But it's interesting to change the parameters of a lot of hand-made coffee. If the gouache ratio I mentioned earlier is 350g:20g, you can try some changes to compare the differences. Or, change the extraction temperature, or change the steaming time. Here, we can do the experiment like the students in the common sense of coffee.

Also, worried about the uneven extraction of the cone, Yoshi made a cylindrical model out of several pieces of plastic and iron to make a hand punch.