Why does steaming fail? what is the use of steaming coffee? why is coffee steaming?

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When hand flushing, we know that we have to steam the coffee powder first, but many people are also defeated by this step. What is the purpose of steaming? And why did your own steaming fail? Today, Qianjie Coffee is here to analyze the reasons for the failure of steaming.

The so-called steaming is the pre-operation of soaking the coffee powder with a small amount of hot water before making the coffee. Roasted coffee beans gradually emit carbon dioxide through small holes in the surface. this process is called awakening or ripening, and the emission rate varies according to the degree of baking, and the exhaust slows down as time goes on. Steaming grasps the moment when hot water comes into contact with the powder to let the gas out quickly.

This seemingly simple small action has a great impact on the finished product. After grinding into coffee powder, the surface area of contact with the outside world increases greatly, and the gas begins to emit. These gases will form an isolation layer between hot water and powder and can not be extracted effectively. And carbon dioxide dissolves in water will have a sour taste, resulting in a bad taste. Infiltration makes the temperature rise and the gas is discharged upward, which makes the surface of the coffee powder protrude and expand as a whole. some people say that the protruding degree of the surface layer of coffee powder represents the freshness of coffee, but no matter whether it is formed or not and its size, the key point is whether the purpose of this action can be achieved.

Three key points of steaming

Whether there is a good steaming effect can be divided into the following three points:

Water quantity

The handling of water depends on the amount that the powder will absorb, generally speaking, the powder will absorb about twice as much water, that is, 1 gram of powder will match 2 grams of water, this ratio can make the powder evenly infiltrated and not flow out too much extract. Too much water will cause the extraction to start early and affect the steaming structure system, and too little will make the powder unable to infiltrate completely. If there are still a large number of bubbles in the extraction, it may be a lack of water, and some parts are not soaked. It will make the extraction uneven taste imbalance, visual conditions to increase or reduce the amount of water.

Water temperature

When brewing coffee, the water temperature will affect the extraction rate, and then change the taste with time, the steaming water temperature is more important to the coffee quality than the control of the water temperature at the beginning of hand brewing, and it is also an important link in the whole process. Steaming is the beginning of the contact between water and powder, and whether the temperature is moderate or not is an important moment to affect the activation of the whole system.

Shallow, hard coffee beans exhaust slowly, will need higher temperature water to accelerate gas emissions, the general water temperature will be controlled at about 90 degrees, although the temperature is high, aroma is more obvious, but also bring out the risk of astringency. The deep-roasted and soft coffee beans are highly active and the gas can be discharged more easily, so the water temperature can be slightly lower than 90 degrees. Adjusting the water temperature according to the baking degree and quality of the beans can make the whole brewing process smoother and bring out the aroma, taste and consistency of the coffee stably.

time

The time of steaming is calculated from the end of water injection, and it is used from 20 seconds to about one minute. It mainly depends on the formation of the hamburger and whether the gas is discharged smoothly. 30 seconds to 40 seconds is a relatively common time, too long steaming will excite the coffee powder, bring out the subsequent bitterness and astringency, too short will infiltrate enough, there is no way to show the flavor.

After long-term observation and summary of Qianjie Coffee, it is found that many friends 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.

You can improve it according to the knowledge about steaming shared with you by Qianjie Coffee today.

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