What is the reason why the steaming of hand-made coffee does not swell? is steaming coffee bad without hamburgers?

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Coffee beans have a taste period. after being stored for a long time, the carbon dioxide in the beans will be reduced a lot, so it is difficult for the coffee powder to expand when steaming.

The roasting degree of coffee also has an effect on the steaming effect. The deeper the coffee is roasted, the more carbon dioxide it contains and the easier it is to expand when steaming. In general, light / medium roasted coffee has less voids than deep roasting, so it contains less carbon dioxide gas, making it more difficult to form steaming packs, especially light roasted coffee.

The higher the water temperature, the less soluble the carbon dioxide in the water, so it is easier to form a stuffy steam package. Of course, if the hand temperature is too high, the bitter taste of coffee is more obvious, generally no more than 93 ℃.

"stuffy steaming" should also consider the thickness of coffee powder, the amount of water injected, the impulse of water injection and whether the coffee powder is smooth in the filter cup.

Coffee powder can not be ground too coarse and too fine, and the thickness should be moderate; the amount of water injected should not be too small, usually 10% of the total water; be careful not to have too much impulse when injecting water, so as to prevent the coffee powder from collapsing and be gentle.

The steaming of coffee refers to the phenomenon that the coffee particles begin to exhaust after absorbing water for the first time, and the surface expands due to the particles pushing each other in the exhaust process, and steam is produced on the surface, so it is not exactly [steaming], but only [steaming].

When the time is lengthened and the steam disappears, the coffee particles will close again from the state of squeezing and pushing away from each other, resulting in a stuffy bad phenomenon.

When brewing coffee, the stuffy state should be avoided, and the action of water supply should be done immediately before the steam disappears, so that the whole coffee will not be suffocated, and only the surface particles will be drained repeatedly.

To sum up, there are many factors affecting steaming, either not steaming up or the coffee is not fresh.

The purpose of steaming is to discharge the carbon dioxide gas from the coffee, so that the coffee powder can be evenly absorbed and saturated, making the subsequent extraction process more sufficient. To achieve the goal of steaming, do not care too much about the formation of a very high steaming package.

The main function of steaming is to release carbon dioxide, which helps water to get flavor from coffee and avoids the negative taste caused by too much carbon dioxide.

In the process of extraction, the coffee powder is dispersed and expanded into a thick filter layer by the first steaming. Through this step, the coffee ingredients can be fully released and the coffee can be extracted effectively.