Introduction of common hand-brewing techniques what is segmented extraction?

It is said that the brewing method of hand-made coffee is divided into eight major schools: one-knife school, three-knife school, volcanic school, meteorite school, Matsuya school, pressing powder school, mixing school and bit-by-bit school. Each of the major schools occupies a seat in the coffee martial arts, and the three-knife school belongs to segmented extraction.

Segmented extraction

This is a relatively common method of cooking, and it is also a way of brewing with one-step flow. To put it simply, segmented extraction is to inject water into several stages, and nothing is more famous in segmented extraction than three-knife flow.

Compared with the one-knife flow, the coffee brewed by the method of segmented extraction will have more rich layers, which can clarify the flavor of the front, middle and back of the coffee, and it is easier to control the water flow from the edge of the filter cup. Reduce the instability in the hand. The downside is that the requirements for grasping the flow rate and controlling the amount of water are relatively high.

Let's first take a look at how the segmented extraction works.

Take [Costa Rica Pilon treatment Plant] as an example.

Filter cup: V60

Water temperature: 90 ℃

Powder weight: 15g

Degree of grinding: BG 5R (pass rate of Chinese standard No. 20 screen 58%)

Powder / water ratio: 1:15

Washing and cooking technique

1. Steam 30 grams of water for 30 seconds. When you see the surface of coffee powder change from wet to dry, it means that the steaming is over.

2. Use a small water flow to slowly inject water around the center to 120 grams, and let the coffee powder soak slightly to make the extraction more uniform.

3. When the water level drops 2 to 3, use the flood flow to flush to the end of 225 grams, so as not to extract the bad taste of the tail section.

For friends who want to try segmented extraction, the most disturbing thing must be when to stop and when to re-inject water.

We can determine when to segment according to the roasting degree of brewing coffee and the rising state of the liquid level during extraction.

| | baking degree |

The shallow roasted beans are not very exuberant in exhaust, when the water in the filter cup becomes more, because there is not enough gas to support the coffee powder, the powder is easy to sink at the bottom after absorbing water, and the injected water is easy to accumulate on the top. unable to stir the coffee powder in the lower layer, so it can be divided into sections and the water can be supplied after the water level drops.

| | rising status of the liquid level |

At the beginning, more water is injected, and when it is found that the water level rises too fast, we can take sections to prolong the cooking time and let the water level drop and then continue to cook, so as to avoid the lack of extraction caused by too fast water flow.

Reasons for Segmentation

Segmented extraction can make the coffee powder wall at the edge of the filter paper not easily broken, and segmented water injection also helps to increase the mixing of coffee powder during brewing, and water injection can penetrate the coffee powder to improve the extraction rate.

How to judge the time point of reinjection?

Sometimes you will see that some baristas just pause for a moment and then continue to inject water, but in fact, this does not make much sense. Usually, when we carry out sectional water injection, we wait for the water level to drop by 1 / 2 or 2 / 3 before water injection. The main reasons are:

1. When the water level drops 1 / 2 or 2 / 3, neither too much water will accumulate in the filter cup, nor will the powder bed be exposed because the water level drops too much, resulting in uneven extraction of coffee powder from the upper and lower layers.

2. After the water level drops, the water flow can directly penetrate the stagnant water to wash and stir the lower layer of powder. If the water level is too high and the impact of the water column is not enough, the upper layer of the coffee powder bed will be overextracted, while the lower layer of coffee powder will not be extracted enough.

Generally speaking, segmented extraction can easily get a cup of coffee with distinct flavor, and we usually use it with V60 filter cup, which is mainly due to the fast flow rate of V60 filter cup. on the other hand, segmented extraction can reduce the lack of extraction caused by fast flow rate to some extent. So if you want to get a rich cup of coffee, you might as well try this technique.