The purpose of coffee steaming coffee steaming and extraction temperature steaming coffee steaming effect of hand brewing coffee steaming

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Steaming is an important step in the brewing process of follicular coffee.

The function of steaming is to let the hot water slowly seep into the center of the coffee powder so that the substance in the coffee powder dissolves in the hot water first to form a high concentration of coffee liquid.

In the second brewing, using the physical phenomenon of the concentration, the high concentration (steamed coffee liquid) moves to the low concentration (hot water) and reaches the middle concentration (the same concentration).

In the process of brewing, due to the continuous addition of hot water and the continuous dripping of coffee liquid, the concentration imbalance between the inner and outer layers of coffee powder is caused.

This is the reason why the flavor of the coffee liquid will be stronger at the beginning and lighter in the second half.

Why does coffee powder swell? Because there is still some space in the coffee powder. And this gap contains air.

And the air will expand when it comes into contact with hot water. The volume will become larger, and as soon as the heat expands, the excess volume of air will be discharged.

And the top layer of coffee powder forms an insulating layer with hot water (surface tension of water).

As a result, hills are formed.

After the above water slowly seeps into the center of the upper coffee powder, the water on the surface decreases (is sucked into the coffee powder).

At this time, the color of the hill becomes dull, and when it begins to collapse, it indicates that the steaming has been completed. You can start the second water injection.

It is important to pay attention to when steaming. Will the water temperature be too high when steaming? The water temperature is too high.. Will cause the air in the coffee powder to expand too much.

So it will make the powder layer expand into a mountain when steaming. Not a hill. There will also be volcanic eruptions. This affects the time when hot water seeps into the center of coffee powder (because there is too much air in the coffee powder. If you can't get out, the hot water can't get in.

The time is extended. The mixed and astringent taste is also easy to dissolve. And. A large amount of hot air is formed because the temperature is too high. It will increase the distance between the coffee powder.

This will make it easy for hot water to pass through.. And the extraction time is too short. Also because there is air in the center of the coffee powder. So the specific gravity is relatively light. It's easy to float on the surface. Unable to form a filter layer at the bottom of the filter. The coffee brewed in this way. The aroma is usually enough (because hot water makes volatile oils evaporate into aroma more quickly), but the taste is not enough. There will be a sense of water

And then. The strength of water injection is also related to the amount. The steaming current is too strong.. Hot water quickly surrounded the coffee powder.. It will make the air in the coffee powder not easy to be discharged. Of course, hot water is not easy to get into the center of coffee powder.

A better way is to use a weaker current. It feels like just putting hot water on the surface of the coffee powder layer.. Let the hot water slowly seep into the coffee powder

The amount of steaming water is too much. It is easy to extract the ingredients from the outer layer of coffee powder. When the outer layer of coffee powder is dissolved, the inner layer of coffee powder is still dry. When hot water seeps into the inner layer of coffee powder.. The miscellaneous and astringent taste of the outer layer of coffee powder also began to dissolve.

And the time of steaming varies according to different beans. For example, deep-baked beans, the exhaust is more exuberant, generally steaming to 25 seconds is almost enough. And shallow baked beans are not afraid of steaming for 30 seconds! The former street gold Manning, for example, steamed for about 25 seconds, you can see the steaming surface from wet to matte, this time represents the end of steaming.

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