Teaching of hand flushing skills | what is the difference between water injection techniques of water cut-off method and continuous water method

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| what is penetrating water

Generally speaking, a penetrating water column means that during the process of water supply, it is expected that every time the water supply is supplied, the water column can pass through the powder layer that has already been drained before, so that the lower non-absorbent particles begin to draw water.

| | height of water column |

The higher the height of the water column, the greater the impact of the water flow, and the difficulty of stable circling will also increase, resulting in greater disturbance in the extraction process, unable to make coffee powder uniform extraction, resulting in increased astringent flavor.

If the height of the water column is too low, the hand punch can easily hit the filter cup, but if you use low water injection, the penetrating water

| Why does the water supply need more and more each time?

When the particles come into contact with the hot water we give, there will be two separate things, the particles absorbing water and pushing the gas out. Now let's talk about the two topics separately.

Objects continue to absorb water will become heavier, coffee particles are no exception, the weight of the particles will sink, relatively light will continue on top, until the particles in the filter cup gradually saturated, the specific gravity is larger than water, will fall to the bottom of the filter cup.

Because the exhaust between the particles will push each other to create a space, and the state of the particles after absorbing water and the disturbance caused by the water supply will cause the so-called potential difference, the reason is that the coffee particles in the filter cup cannot have different weight of the same grain, so the heavier ones are at the bottom and the lighter ones are at the top.

Now it is more clear that the relationship between particles and water, heavier particles will be deposited at the bottom, if the amount of water supply can not become larger and larger, the particles accumulated at the bottom can not be disturbed, continue to soak, for a long time will become the so-called excessive immersion

| how to judge water injection by the speed at which the water level falls?

When the water supply reaches the bottom, the particles at the bottom begin to expand, and as the water at the bottom runs out, the whole powder layer decreases.

When the coffee powder particles do not absorb much water at first, because the coffee powder particles are lighter, most of the coffee powder will float on the water surface, and as the water level drops, the surface will look like a bowl or a U-shaped with a large opening.

The speed at which the water level drops represents the amount of draught of coffee powder particles. Because the coffee powder in the filter cup is lighter than water at first, the coffee powder particles will sink more slowly than the water flow, and when the coffee powder eats more water, the weight becomes heavier. Coffee powder particles will quickly reach the bottom of the filter cup and cause blockage, which slows down or even stagnates the water level.

When the water level falls too fast, there is no need to add water. Because when the current falls faster than the particles, it means that the water is scouring the coffee powder particles, so that the coffee powder particles are not in a static state.

When the water level drops slowly, it means that coffee powder particles begin to deposit at the bottom, causing blockage and causing the water level to fall slowly.

When the water level stops falling, it means that the bottom is completely blocked, and the coffee powder particles are also soaked in the water, and once this situation continues for too long, the bitter taste will follow.

Therefore, at the time point of adding water, when the water level is delayed or the water level is no longer falling, the penetrating water begins to be added.

| | difference between water cut-off method and continuous water method |

Water cut-off method (flavor tendency: more mellow)

Sequence: first water injection, steaming →, second water injection, → third water injection (→ fourth water injection)

The amount of water injection ─ increases from small to large, and the speed is slow at first and then fast.

The so-called "cut off water" is to interrupt water injection in the process of hand flushing. Until the water level drops to a certain extent, continue to inject water and repeat this action several times. Those who support the water cut-off believe that stopping water injection during hand flushing can prolong the extraction time of coffee powder, so that the aromatic substances in coffee powder can be fully extracted, and the coffee will taste stronger and taste more layered.

One of the key steps in making coffee by hand is "steaming". In fact, what we often hear about steaming is to cut off the water for the first time.

Continuous water method (flavor tendency: more refreshing)

Sequence: steam → water injection once

The amount of water injection ─ increases gradually from small to small, and the speed is slow at first and then moderate.

The "continuous water method", as its name implies, is in the process of not interrupting water injection except for steaming off water. Draw a circle from the inside to the outside in the size of a 50-yuan coin. in order to keep the water surface at a certain height, it should be dense and slow in the center, and fast when circling the outer circle, so as to maintain a consistent and uniform extraction rate.

In a word, when using the continuous water method, the control of the flow rate is the key. In the way of continuous water, the flavor of coffee is more elegant and refreshing than that of cut off water.

Is hand-made coffee really good? Why does coffee smell better than it tastes?