The principle of hand extraction is not a simple hot water flushing which of these factors affect the concentration of coffee.

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Extraction principle and concentration factors of Qianjie-hand-brewed coffee

In fact, the principle of hand-brewing coffee is "dissolve" and "spread".

After roasting, coffee beans undergo a chemical reaction to produce coffee ingredients that emit coffee aroma and flavor. in order to extract these coffee ingredients, you need to grind the coffee into powder and then slowly inject water to dissolve the substance in the coffee, which is called "dissolving".

With the help of "steaming", "stirring" and "shaking the sharing pot of coffee liquid" in the extraction (there will be a concentration difference in the dissolving process of water injection, shaking the sharing pot after extraction in order to make the coffee concentration uniform) to dissolve it as "diffusion".

From the beginning to the end, hand-brewed coffee is a process of letting water pass through coffee powder quickly and evenly. Unlike espresso, hand-brewed coffee is a pressure-free free-fall extraction. In this process, the speed of water passing through coffee powder is the key to extraction. We often say that there are more reasons for over-extraction and insufficient extraction.

Water is permeated and extracted through the gaps between coffee particles.

If the grinding is too fine, it produces a sand effect, and the water permeates less space, affecting the flow rate; the shorter the baking time is, the deeper the coffee is roasted during the fresh cycle, or the deeper the coffee is roasted, the higher the content of carbon dioxide inside the coffee will be. During extraction, coffee will release a large amount of carbon dioxide, which will isolate the gaps between coffee particles and form a filter layer to allow water to pass through to produce extraction. Then the higher the water temperature, the higher the amount of carbon dioxide produced and released, which increases the speed at which the water passes through, while the speed at which it passes through is relatively slow.

The same is true of coffee. In the process of coffee extraction, the most ingredients we can soak or extract are only 30%, and the remaining 70% are not analyzed, so in these 30% soluble substances, we only need about 12% of the ingredients. More than 12% of the ingredients can be counted as over-extraction, which we do not need. It will cause excessive bitterness or superfluous odor, similar to the smell of dirt and leaves. On the contrary, the lack of extraction is due to the fact that the water penetrates the coffee powder too fast and the precipitate is less, resulting in a light and sour taste of the coffee.

In fact, the factors that affect the concentration of hand-brewed coffee are nothing more than the various factors of extraction. For example, water temperature, grinding degree, manipulation, roasting degree and so on, each factor will affect the final extraction concentration of coffee, and the concentration is too high or too low is deviated from the final concentration range.

Knowledge: coffee beans are the fruits of coffee trees, which belong to perennial evergreen shrubs or small trees of Rubiaceae.

In short: Qianjie is a coffee research hall, happy to share the knowledge about coffee with you, we share unreservedly just to make more friends fall in love with coffee, and there will be three low-discount coffee activities every month. The reason is that Qianjie wants to make more friends drink the best coffee at the lowest price, which has been Qianjie's tenet for 6 years!

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