Analysis on the skills of hand-brewing Coffee Water injection process Why do you want to inject water in a circle to make coffee?

Making coffee by hand and injecting water around the circle is almost a basic operation. But have you ever wondered why it is injected in a circle? Qianjie will discuss this issue with you today.

The first reason is to improve the extraction rate, which is also the reason that many people think of in the first place. In daily life, if you make instant coffee or granules and soak them with hot water alone, chances are that they will not all dissolve, so we will stir them with a small spoon to make them all blend into the water.

The same is true of hand-brewing coffee, which needs to be "stirred" to release more coffee. But the coffee is not stirred with a small spoon, but stirred with a column of water. This reason explains why you don't inject water at a fixed point, but stirring is not necessarily just injecting water in a circle. The method of making siphon pot coffee is not only stirring in a circle, but also cross stirring, ∞ stirring and Z stirring.

So the second reason needs to explain why hand-brewed coffee only chooses to circle. The reason is that we are not as good at manipulating water columns as wooden sticks (spoons). Using other forms of mixing to inject water, it is extremely easy to produce turbulence (disturbance). Generally speaking, there are two main reasons why coffee is easy to produce turbulence. The first is that the gas is not discharged during steaming, and the gas is released to produce turbulence during subsequent water injection. The second is the turbulence caused by irregular mixing. At present, this kind of obvious turbulence is rarely seen in unidirectional circular water injection. Of course, circular water injection is also necessary to find the right way to use, as in the case of "stirring granules", if we want the particles to dissolve faster, we should increase the stirring efforts. The same is true of hand-brewed coffee, which can be stirred more strongly by speeding up the speed of the circle. But the difference is that we don't want all the substances in the coffee particles to dissolve, we just need to dissolve the flavor substances that taste better (18-22% of the extraction rate). Therefore, we should control the stirring intensity and improve the extraction rate while avoiding over-extraction. As for how to inject water around the circle, Qianjie suggests using the simplest method to achieve "no turbulence and uniform extraction". The use of slower circular water injection, better control the angle of the water column, the stability will be better, the circle can be "mosquito-repellent incense" slowly from the middle to the outside, and then slowly back to the center.

In this way, beginners can better control the strength and time of mixing, thus reducing a lot of "rollover" incidents. There are many ways to inject water. Please start with the simplest and most useful one.