Why is there no hamburger in steaming? why does steaming not swell? How to inject water into steaming?

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Recently, a fan asked the editor: editor, why is there no hamburger in the coffee and beans I just bought?

What are "steaming" and "hamburger"?

[steaming] in English instructions, it is often expressed as Bloom, which refers to the preparatory action of wetting a small amount of hot water evenly on the surface of coffee powder during hand flushing before formal water injection.

Steaming is a very important step in the process of making hand-brewed coffee. Good steaming can fully infiltrate the coffee powder and activate the coffee activity, thus making the coffee extraction process more smooth. Some stuffy steams with obvious steaming effect and large exhaust capacity will make the coffee method bulge in the shape of [hamburger]. Generally speaking, for beginners, the effect of steaming can be judged by observing the shape of "hamburger".

How to correctly inject water and steam?

"are there any tricks and tricks for steaming water injection? is there anything particular about it?

In the editor's long-term observation and summary, many friends will mainly have the following problems when steaming and injecting water:

1. Uneven water injection.

This situation is quite common for beginners, and it is easy to happen when you are not familiar with the hand flushing pot: the water column is thin and thick, the circle is not round, and the water injection is asymmetrical, resulting in water flooding out of places with more water, penetrating filter paper; places with less water can not be completely wet with coffee powder, and the steaming effect is greatly reduced. Eventually lead to water injection extraction, part of the extraction is excessive, part of the extraction is insufficient, the flavor is messy, it is easy to appear astringent taste.

2. Water injection is too gentle.

On the whole, this situation should be rare, and even if there is, it is not obvious, mainly when using thin-nosed pots:

①, because of nervousness or inadaptability, some people will inject water very carefully in the face of some special (expensive) beans, fearing that they will inadvertently screw up a pot of good beans, but they do not realize that the more careful they are, the more careful they are, the more prone to problems. When you inject water very gently, or listen to the so-called "paving" saying, when injecting water, there is not enough strength to let the water penetrate the surface powder layer, but moist the surface, so that the water can only rely on capillarity and gravity to infiltrate into the deep layer. At this time, the time for steaming water to seep from the surface to the bottom will be prolonged, and some of the water will spread from the surface and flow away from the edge ribs. And reduce the actual amount of water obtained by steaming coffee powder, the effect of steaming will naturally be greatly reduced.

②, powder is too fine or too much. If the powder is too fine, the particles will be tight, and the speed of water infiltration will be very slow, and it is easy to diffuse. If there is too much powder, the powder layer will be thick. if the penetration is not strong enough, the water will stay on the surface, and finally it will still be the result of water slipping away from the edge.

In view of the problem of uneven water injection, the editor's suggestion is to practice more. Practice falling into the water-- circle-- stop movement, to ensure that the whole column of water is stable, as vertical as possible, within the range of steaming water, the whole set from the inside to the outside, and from the outside, the movement to return to the center should be smooth and stable. If the hand-flushing pot is really difficult to control, consider changing to a convenient pot. After all, beans are not cheap.

There is another situation that can easily make people uncomfortable when steaming: bubbling. What is the general reason for the appearance of air bubbles?

①, water injection too much too quickly, the water becomes a film, from the upper layer wrapped in the lower layer of dry powder, and slowly soak the lower layer, causing exhaust, when the tension of the water conflicts with the rising strength of the gas, it is easy to form air bubbles.

②, or uneven water injection, when the water injection is uneven, part of the wet powder wraps the dry powder and slowly permeates, the exhaust will not be smooth, and the water will flow downwards and the gas will rise due to gravity, which will naturally lead to conflict.

So, in addition to the aesthetic factors, the emergence of large bubbles during steaming has an impact on the overall steaming effect?

The editor's view is: it has an impact, but it is not as exaggerated as the visual effects.

With regard to the intensity of water injection, the editor has two suggestions:

①, to increase the intensity of water injection, you can start from two aspects: the size of the water column and the height of water injection. After all, some small-mouth pots are really only suitable for fine water flow. When the water flow is large, it is easy to tilt the water column. At this time, increase the water injection height and let the gravity acceleration provide you with enough penetration. Of course, do not splash.

②, appropriately increase the amount of water and time of steaming. If the soldiers come to cover up the water and cover the soil, since the penetration is not enough, the actual amount of steaming will be reduced and the speed will be slowed down, so just increase the amount of water and prolong the steaming time.

Let's get back to our theme: why doesn't some coffee swell when steaming, or even "hamburgers"?

The factors affecting the degree of steaming expansion:

1. The freshness of coffee beans.

As mentioned earlier, steaming is for exhaust, so the fresh coffee beans contain more gas (mainly carbon dioxide), and the more "hamburgers" swell when steaming naturally. If you don't see an expanding "hamburger" during stewing, it means that the coffee may have been roasted for too long, causing the carbon dioxide in the cells inside the beans to be released naturally, which means that the beans are no longer fresh.

2. The roasting degree of coffee beans.

To a certain extent, the deeper the roast, the more obvious the breathing effect of the coffee beans, the more gas will be released, and vice versa. For a lightly roasted bean, the caramelization (or carbonization) is not as deep as the deep-roasted coffee, and the reaction produces fewer metabolites (released gas), so the respiration is weaker, so it is normal that the steaming effect is not obvious or there is no "hamburger" effect.

3. The grinding degree of coffee powder.

It is not difficult to understand that if the grinding is too rough, the surface area of water in contact with coffee powder will be small, and the exhaust effect will naturally be weak. if the grinding degree is particularly rough, there will be no "hamburger" in any case.

Why do hamburgers always collapse quickly?

1. Oversteaming

2. Excessive water injection after steaming.

3. Bean baking is relatively shallow.

It collapses soon after steaming a hamburger, which should be related to the technique, such as strong water injection to break the powder layer or too much water injection. Steaming and injecting water is best to draw a circle from the center; when steaming, the amount of water is too little, the coffee powder at the bottom and edge of the filter cup is still dry, and when reinjecting water, it is especially easy to produce large "volcanic bubbles" when it is hot.