Coffee brewing by hand: analysis and treatment of the "channel effect" of hand-brewed coffee

Previously, we only knew the "channel effect" that we often encountered in espresso extraction-that is, during the extraction process, the flow caused by grinding degree, powder distribution, packing and uneven water distribution from the machine outlet head passes through the weakest part of coffee pressed powder, making the espresso extraction uneven, the part being overextracted, the rest underextracted, and often getting a cup of strongly stimulating but thin taste espresso.

Today, it is suddenly found that this channel effect also exists in hand-brewed coffee, and it is also a big reason for the bitter taste, more miscellaneous flavor and insufficient overall balance of coffee.

We have to start with the three cups of hand bubble with the boss and my brother this morning.

East Timor, which was just baked yesterday, the boss made a cup: the entrance is refreshing, the overall taste is soft and balanced, bitter and sweet, even the aftertaste is so clean and crisp, with a little bit of shallow taste.

The same degree of grinding and water temperature. I made one, too. Although it lacks the soft feeling of the boss, the whole is still relatively pure, and it also has a balanced harmony of bitterness and bitterness, but the concentration is higher than that of the boss's cup. So the overall sense of clarity is a little less-- like a sudden wind blowing half-scattered broken clouds in a clear blue sky.

The younger brother made another drink. The obvious point is that the strong bitterness comes out, and it clings to the tongue after the entrance and lingers at the root of the tongue for a long time. Because of this bitter taste, other tastes in the cup are also masked, and the tongue cannot easily feel other flavors after being electrocuted by this bitter taste. so the overall taste of this cup gives the impression that the bitter taste is obvious and the taste is thin and not rich and balanced.

I have encountered this problem before, and recently my younger brother is also trapped in this "bottleneck". One cup, two cups, three, four, five or six cups still can not get rid of this annoying bitterness. The younger brother kept practicing, and there was a long line of coffee cups on the bar. Suddenly saw the word "channel effect" in a post, and hurriedly turned to the bar to look at the brewed powder. Sure enough, the sunken part of my younger brother's powder was always on one side, and when it was serious, it would leave an obvious hole on one side, and the water went straight through the hole, accompanied by the bitter taste and miscellaneous taste of the coffee powder around the hole, and the farther away it was from the hole. The more it is not extracted-which is why the whole cup of coffee looks so thin and insipid.

Back to sum up: in fact, although hand-brewed coffee and espresso have great differences in the way of extraction, but both are the process of water passing through the coffee powder to extract the flavor components in the coffee powder. In terms of mechanical principle, the strength and uniformity of the water flow in the extraction are a major factor affecting the taste. The coffee powder layer in the filter of hand-brewed coffee is equivalent to espresso pressed powder, but because it is extracted by atmospheric water without pressing powder. Therefore, in order to ensure that the water can be extracted evenly when passing through the coffee powder, the thickness of the grinding powder, the uniformity of the cloth powder and the uniformity and stability of the watering flow and flow velocity also affect the taste of the coffee. I have seen before that the powder after brewing is as smooth and glossy as a hill in the moonlight, which may be the same as the smooth pressed powder after espresso extraction.

Oh, the original seems to be entirely based on the feeling of hand-brewed coffee also contains such a "scientific principle" ah! But I still like to make hand bubble in a humane way and treat every cup of coffee, that is fraternity-treat every bean, every coffee powder with the same love, and have a heart-to-heart conversation with all the coffee powder in front of me. In fact, the so-called spring breeze and rain can be fully reflected in the brewing process of a cup of coffee: steaming as gently as the spring breeze awakens every sleeping coffee powder, and then the fine spring rain sneaks into the heart of the coffee with the wind, impartial and perfectly releases the aroma factors of each grain of coffee powder into that cup of essence coffee-that is the most beautiful nectar in spring.

Source:

The blog of the world of coffee with two bottles of water