Basic knowledge of hand-brewed coffee purpose tips on the cause of steaming of hand-brewed coffee

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Stuffy steam

Steaming sounds like: coffee is dry, you get it wet. The reason you need to think of it as a complete phase is that it is not as simple as it sounds. One of the main by-products of roasted coffee (you don't think coffee beans are brown, do you?) It's carbon dioxide gas. For lightly roasted coffee, carbon dioxide is trapped in the cellular structure of the beans and slowly oozes out after a few weeks. For dark roasted coffee, the roasting process explodes a hole in each cell, and most of the carbon dioxide is released within a few days. This dark roasting feature (coffee roasted past the "second crack" stage) is also why I recommend different specifications of coffee, while dark roasting is more efficient.

When you flush coffee grounds with hot water, carbon dioxide escapes and bubbles appear. The problem is that if carbon dioxide gas is discharged, water cannot enter. I like to imagine people shopping on Black Friday. If you open the door at the same time as a panicked fire drill, you may make a mess. In other words, unless all the people who want to come in wait until all those who want to go out are out.

When you start brewing pourover, you need to add enough brewing water to wet all the coffee grounds, and then it's best to stop and let the gas escape for about 30 seconds. You will see the bottom of the coffee grounds expand, forming what coffee experts call "steaming".

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