Understand why hand brewing should be steamed. | how long does it take for hand brewing coffee to be steamed?

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Steaming Bloom refers to the preparatory action of wetting the surface of coffee powder evenly with a small amount of hot water during hand flushing before formal water injection.

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 concentration is the same).

Good steaming can make coffee powder fully infiltrate and activate coffee activity, thus making the coffee extraction process more smooth, some steaming with obvious steaming effect and large exhaust capacity.

If the water supply is too much, the water will flow directly, it is difficult to play the role of steaming, and because it is not fully steamed and the extraction is insufficient, in fact, it only plays the role of diluting the coffee liquid. So we usually use one to two times the amount of powder to steam.

Because the water absorption rate of coffee powder is about 1.5-2 times the weight of powder, so usually if it is 15 grams of powder, we will use about 30 grams of water for steaming.

Twice the weight of the water can completely soak the coffee powder, if there is not enough water when steaming, some coffee powder can not fully contact with the water exhaust, so it is easy to lack extraction; and if the water supply is too much when steaming, it will cause the hot water in the front steaming part to not extract enough coffee ingredients, but dilute the whole cup of coffee, affecting the overall alcohol thickness, layering and final flavor performance of the coffee.

In addition, the astringency of coffee is mostly caused by the long extraction time, but steaming will still become the source of astringency, and this astringency will be felt from the entrance to swallowing, making your flavor flaw on the surface.

Steaming time

"steaming" is a state, it is in the process of coffee extraction, the most beautiful scene. When you pour hot water into freshly ground coffee, it begins to bulge and steam. Water causes coffee powder containing carbon dioxide to start to exhaust, releasing carbon dioxide.

Because carbon dioxide is a barrier that prevents water from extracting all soluble solids from coffee, it must be discharged first.

The exhaust during "steaming" is the same as that of Coca-Cola or Fanta. Carbonation will cause the powder bed of coffee to expand and may grow to twice its original size. "steaming" is considered to be an important start for brewing coffee.

You can use water twice the weight of coffee powder for steaming, and 50g of water is used for steaming in Miya Zhe's "four or six rules".

The time of steaming depends on the freshness of the coffee you use. Freshly roasted coffee requires longer steaming time (30-45 seconds), while beans require longer steaming time (15-30 seconds). Steaming time also depends on the roasting degree of coffee beans-lighter roasted beans require longer steaming time, while deeper roasted coffee requires shorter steaming time to avoid over-extraction.

Just like warming up before exercise, in order to do your best to reach every muscle in the body so that they can reach their full potential, you must first awaken your muscles with a warm-up. Similarly, steaming enables coffee to reach its full potential, helping to create a uniform extraction and uniform coffee powder bed.

It may be so tedious and complicated to say, but when you pay attention to these details habitually, they will become your habit. You are not far from extracting a good cup of coffee.

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