How to time the cooking by hand? What's the difference between one-size-fits-all flow and segmented extraction?

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[question 1]

Q: why does milk make foam?

The basic principle of milk foaming is to use steam to hit the milk, so that the liquid milk into the air, using the surface tension of milk protein to form many small foams, so that the liquid milk volume expansion, into a foam-like milk bubble.

In the process of foaming, lactose dissolves in milk because of rising temperature, and uses foaming to seal lactose in milk, while the function of milk fat is to make these small foams form a stable state, so that when these milk bubbles are drunk, the fine foam will burst in the mouth, so that the taste and aromatic substances have a better magnifying effect, so that the milk produces a sweet and thick taste and taste. And in the fusion with coffee, the adhesion between molecules will be relatively strong, so that the full combination of coffee and milk, so that the special properties of coffee and milk are highlighted, and completely integrated together to complement each other.

[question 2]

Q: what's the difference between one-size-fits-all flow and segmented hand punching?

To put it simply, one-size-fits-all flow: after steaming, only one uninterrupted injection of water is done, while segmented extraction is to inject a section of water into several stages after steaming.

One knife stream

The name sounds interesting, much like a martial arts move in a martial arts novel. The essence of this cooking technique is to do only one uninterrupted injection of water after steaming.

The coffee powder can be continuously soaked in water, the retention liquid can fully release the aromatic substances in the coffee powder, the flow velocity increases continuously, and the water flow is reduced before the water overflows the filter cup.

The main control of one-cut flow is the amount of water injection and flow rate, can achieve the whole section without losing the sense of balance, inappropriate water injection, will destroy the overall sense of balance of coffee.

The main purpose of this method is to maintain a peaceful flavor and a sense of balance. What is not so good is that, because the water injection technique is not well controlled, the water falls through the filter paper on the edge in the upper position where there is no coffee powder, so that the coffee produced may be underextracted.

Segmented extraction

As the name implies, water injection is divided into several stages. Inject a section of water into two or three stages after steaming.

Segmented extraction can get richer layers than one-knife flow, and can clarify the flavor of the front, middle and back stages of coffee. The practice is to increase the amount of water each time after steaming, usually when the coffee liquid is about to drop to the surface of the powder layer, and use small, medium and large water flow to do three-stage extraction. However, segmented extraction will have higher requirements for the flow rate and flow rate of water.

[question 3]

Q: does the cooking time start with steaming or steaming?

Let's watch a video first:

The above is the normal process of stifling water injection demonstrated by Xiaobian. As can be seen from the whole video, the amount of water injected by Xiaobian is 30 grams, and the time will be about 10 seconds. That is to say, 10 seconds of water injection + 30 seconds of steaming = 40 seconds; if the timing starts from the beginning of water injection, then 10 seconds of water injection + 20 seconds of steaming = 30 seconds will be less than my default 30 seconds of steaming.

In fact, what is the effect of the steaming time of 10 seconds on the extraction of coffee?

The editor steamed with [El Salvador] for 20 seconds and 30 seconds respectively. In order to reduce the error, the editor completed the experiment with a smart cup to see what would be different.

In fact, the difference between the two drinks is not big, only some slight changes, if not two drinks at the same time comparison is not very obvious.

Generally speaking, as long as the water temperature and grinding are correct, the steaming operation is not wrong, and the slight deviation of the steaming time (less than 10 seconds) will not change so obviously for the whole hand flushing result.

Well, that's all for today's novice Q & A series. I hope I can help you. If you have any questions, you are welcome to come and communicate with us!