What is the purpose of steaming hand coffee? there are several factors that affect the steaming effect of hand coffee.

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Qianjie-Hand brewed coffee steamed purpose profile

Do you really understand what he means?

Hand-brewed coffee is a simultaneous process of flavor extraction + filtration, and the extraction takes place centered on the position of pouring water. The more water, the more extraction. Newly roasted coffee beans will produce more carbon dioxide, which is not conducive to the full contact between water and coffee powder to complete the extraction, so it is necessary to stew first to avoid uneven extraction of coffee powder and affect efficiency.

Bloom, so-called steaming, is the pre-operation of soaking coffee grounds with a small amount of hot water before brewing coffee. Roasted coffee beans gradually emit carbon dioxide through small holes in the surface. This process is called waking beans or ripening. According to the degree of roasting, there are different emission rates. As time goes by, the exhaust will slow down. Steaming grasps the moment when hot water comes into contact with the powder, allowing the gas to be quickly exhausted.

This seemingly simple small action greatly affects the finished product. After grinding into coffee powder, the surface area in 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 cannot be effectively extracted. Moreover, carbon dioxide dissolved in water will have a sour taste, resulting in a bad taste. Infiltration allows the temperature to rise, and the gas is discharged upward, so that the surface of the coffee powder protrudes and the whole expands. Some people say that the surface protrusion of the coffee powder represents the freshness of the coffee, but regardless of whether it is formed or not and how large it is, the key point is whether it can achieve the purpose of this action.

Usually the stewing time is 20-30 seconds. Once the stewing time is over, hot water should be injected immediately. The judgment point of the end is when the powder expands the most and has not collapsed. If you have a scale, add hot water twice the weight of the powder, or use only a small amount of water to slightly wet the coffee powder.

Steaming has two positive effects on coffee flavor:

First of all, carbon dioxide has a sour taste. If the carbon dioxide emitted from coffee is not exhausted during steaming, it will make coffee have a bad sour taste.

Second, carbon dioxide will block the contact between water and coffee, only the discharge of carbon dioxide, in order to more complete dissolution of coffee aroma and oil.

As long as there is gas in the coffee powder, it will interfere with the extraction of coffee substances by water and will make the extracted coffee have a pungent sour taste.

The next time you make your own coffee, remember to steam it first to let it breathe in order to grasp the fascinating flavor of coffee and avoid the negative flavor and sourness caused by carbon dioxide.

Knowledge expansion: In the world of coffee brewing, it is most important to restore the flavor of beans as much as possible. In order to achieve this goal, every link can be full of creativity, so there are many kinds of brewing methods, which are what we often call hand brewing genre.

In brief: Qianjie is a coffee research center, happy to share knowledge about coffee with everyone, we share it without reservation only to let more friends fall in love with coffee, and there will be 3 low discount coffee activities every month, because Qianjie wants to let more friends drink the best coffee at the lowest price, which is also the purpose of Qianjie for 6 years!

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