What is the steaming of baking? What's the difference between baking and hand steaming?

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In the process of baking beans, if the throttle is closed (small) or a pot is added to the lid, a large amount of water vapor will accumulate in the baking room, but compared with the pressure caused by water vaporization inside the beans, it is really negligible (in terms of pressure difference, it may not even be 1/1000), while the beans become soft by heat (from glass state to rubber state), which is closer to the physical change after heating. It is not steamed like steamed bread.

In the process of hand flushing, we will first wet the coffee powder with a little water, a process called steaming. "steaming" in hand is a process in which coffee powder releases carbon dioxide quickly after it comes into contact with water, known as bloom in English, and blossoms agree that it occurs only when brewing fresh coffee.

Stuffy steam

In the first stage of making coffee, you only need to inject a little hot water first. when the hot water comes into contact with the coffee powder, it will accelerate the carbon dioxide emission of the coffee powder, and you can clearly see that the surface of the coffee powder is bubbling, but once again, the degree of expansion does not represent the freshness of the coffee.

The deeper coffee has a lower moisture content, and when it comes into contact with water, it will absorb water and release more gas, thus allowing a greater degree of expansion.

Shallow coffee has a higher moisture content, less water absorption and less gas release when it comes into contact with water, so it is less likely to expand.

This program is called "Bloom".

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