How to make coffee by hand?

Guide reading

Hand coffee is actually the use of water to wash coffee powder to get a cup of delicious coffee liquid. As for how to inject water to make coffee, even if this barista has learned what to share.

How to inject water?

We can see that most baristas make coffee in circles, but in fact, this way of filling water is closely related to the form of the filter cup. Now the tapered filter cup widely used is funnel-shaped, wide at the top and narrow at the bottom, while the purpose of water injection around the circle is to make the coffee powder in the filter cup extracted evenly and is not easy to produce turbulence. You can try that if the middle water injection is used in brewing coffee, as long as the water column is not vertical, it will produce turbulence and it is difficult to ensure uniform extraction.

Clockwise or counterclockwise?

Many buddies who have just entered the pit immediately fall into another blind spot, that is, the direction of the circle, after learning how to inject water around the circle. In theory, water injection will not change much either clockwise or counterclockwise. The V60 filter cup will be special because its rib structure is not a symmetrical structure, but a structure extending counterclockwise from the bottom.

Therefore, when circling clockwise, the water flows along the default line of the swirling ribs to the center of the filter cup, and the path is short; when circling counterclockwise, the water moves counterclockwise due to inertia, and flows along the rib direction to the center of the filter cup after touching the ribs, the path through which the water passes will be longer. Therefore, it will be thought that counterclockwise water injection will be higher than clockwise extraction rate. But in fact, the interaction of each parameter, clockwise and counterclockwise water injection will not have a qualitative change.

Control of flow size

For the first time, we define the concept of flow size. In the front street, the velocity 5g/s is defined as a general flow, then lower than 5g/s is called small flow, and greater than 5g/s is called large flow. The large water flow has a strong scouring ability, but the duration is short. If the coffee is used in the whole process, it will show clean and outstanding aroma. Small water scouring ability is weak, soaking ability is strong (long time), if the whole use of small water coffee will show layers, solid taste.

In our daily brewing, large water and small water will be used together, for example, to brew mellow coffee, we can first use large water to pull up the powder layer, and then use small water to soak around to extract mellow coffee. For example, if you want to express the explosive flavor of Rosa coffee, you can first brew a rich front section with a small water flow, and then stir it with a large water flow to improve the aroma of the coffee.

Distribution scheme of water injection

The most important thing for everyone is how to allocate the water injection plan, how many sections it is divided into, and how much water is injected into each section. Whether it is one-step flow or two-stage or three-stage type, the greatest influence is that even if the extraction time is long, that is, when the amount of water is fixed, the more segments, the more substances extracted from coffee, the richer flavor and the possibility of miscellaneous flavor; on the contrary.

As for the choice of the amount of water injected into each section, we can observe the ideal extraction diagram. With the passage of time, the dissolution rate of sweet and sour substances tends to slow down, while the bitter substances gradually increase. Therefore, if more water is allocated in the middle and front section, the more acid and sweet substances are extracted, the less bitter substances are. If more water is distributed in the middle and back, the bitter substance will be extracted more easily. Qianjie has described in a previous article that appropriate bitter substances are conducive to the layering and flavor of a cup of coffee.