Coffee review

Sharing the basic logic of hand-brewed coffee: How to improve the level of coffee with segmented brewing?

Published: 2024-07-21 Author:
Last Updated: 2024/07/21, People often say that there are thousands of brewing techniques, but only segmentation is the most reliable. I don't know if you have ever been curious about this question since you learned to brew by hand. Everyone always emphasizes that segmented extraction can better enhance the layering of coffee. So each stage of water injection is actually responsible for extracting which part of the coffee. What about the flavor? heart

It is often said that there are thousands of cooking methods, only the section is the most reliable. I don't know if you are learning to flush by hand, have you ever been curious about such a question? people always emphasize that segmented extraction can better improve the hierarchical sense of coffee, so each stage of water injection is actually responsible for extracting which part of the flavor of the coffee?

The heart is not as good as action. In the front street below, take apart each extraction stage in a pot of hand-brewed coffee, and then compare it one by one to see what kind of flavor it has.

The flavor performance of different extraction stages in order to clearly identify the flavor released at different stages, Qianjie prepared a light-roasted sour coffee and a moderately roasted nut coffee as brewing objects, and used a four-stage method to inject water, and then use four pre-heated sharing pots to receive each section of coffee liquid.

Coffee beans: Kenya Kirin Yaga AA & Qianjie Yunnan Sun Iron pickup Powder: 16g Total Water injection: 240ml (30ml, 70ml, 70ml, 70ml) Grinding degree: EK43 10 scale (20 sieve pass rate 80%) Water temperature: 90 ℃ filter Cup: Hario V60: 01

Water injection technique: four-stage type

Specific operation: first with 30ml hot water into the first section for steaming for 30 seconds, about 25 seconds, quickly change the second sharing pot, while clearing the weight of the electronic scale to zero.

At the end of steaming, the second section is injected in a circle from the inside to the outside, and the powder layer is raised at the same time. The target amount of water is 70ml. When the water in the filter cup is about to drain, immediately put on the third sharing pot, return the weight to zero, then continue to inject the third section of water, and then wait for the coffee liquid to be filtered. Keep repeating for 3 times until all the target water has been injected, and the coffee liquid of four different stages in the two groups can be obtained smoothly.

Due to a few more "pot changing" and "peeling" movements, the total extraction time will be lengthened. The brewing time of Kenyan coffee is 2 minutes and 18 seconds, while the dripping time of Yunnan iron pickup in front street is 2 minutes and 26 seconds. Next, Qianjie is going to taste and record the flavor one by one, and then mix them all and try them.

Extraction stage

Kenya Kirin Yaga AA

Qianjie Yunnan Sun Iron pickup truck

The first stage (steaming)

Flavor: berries, plums, caramel, strong taste, sour and salty taste

Flavor: nuts, caramel, herbs, the highest concentration, mainly bitter and salty taste

The second paragraph

Flavor: grape, black brin, black plum juice, cranberry, light flower, obvious fruit juice, but the concentration is still high, the aftertaste is slightly bitter

Flavor: hazelnut cookies, chocolate, Sugar cane juice, red, clear flavor, but heavy aroma, short finish

The third paragraph

Flavor: black plum, Hawthorn, citrus, round tea, light and elegant aroma, sweet taste

Flavor: Balanmu, Sydney, sweet melon and fruit, mugi-cha, slightly lower concentration, weak flavor

The fourth paragraph

Flavor: olive acid, green tea tail rhyme, the overall taste is light, the aroma is thin

Flavor: almonds, herbs, tea, the lowest concentration, like Pu'er tea which has been brewed a lot.

Mix all

Flavor: dried cranberries, black grapes, Sydney tea, well-balanced taste, moderate sweet and sour, good fruit juice

Flavor: hazelnut, sugar cane, cream, caramel biscuits, nectarine, melon, rich aroma, sweet, sour and bitter balance, full layers

What substances are mainly extracted from each stage of water injection?

In the process of segmented extraction, in addition to concentration is one of the main factors, the soluble substances that provide flavor will also change subtly with the passage of time.

Combined with the above comparative experiments, the first stage of steaming has two functions: one is to provide the process of exhaust and water absorption for coffee powder, so that it can be taken evenly later, and it is also the first step to obtain sour taste, but because the amount of water injected is less, so this part of the coffee liquid concentration is very high, showing a turbid and salty flavor.

The hot water injected in paragraphs 2 and 3 is responsible for extracting the fruit acid part of the coffee and the main aroma substances. Fruit acid beans will release a large number of ingredients expressing flower aroma and fruit acid at this stage. At this time, the medium-roasted coffee tends to give priority to dissolving caramelized aroma and some fruit acid substances.

When it comes to the last stage of water scouring, the coffee will release more concentrated soluble substances that express mellow and sweet taste. But as the extraction process continues, even beyond the ideal brewing time (more than 2 minutes and 30 seconds), those wood-flavored, miscellaneous, bitter, astringent end ingredients will come out at this time, that is, we often say that coffee is too extractive.

Application of Cooking Logic

Now that we have identified the flavor substances that are mainly responsible for each stage, the remaining task is to apply these extraction rules to the actual cooking cases.

For example, when we have a bag of coffee beans with a very sweet flavor description, if we want to fully extract the sweetness from the coffee, we need to improve the extraction rate within the range of controlling and avoiding the extraction, by raising the water temperature, fine grinding, prolonging the brewing time, or increasing the water injection in the back section.

If you want to flush out the juicy feeling of a bean, under the usual parameters of brewing shallow roasted coffee, you can focus on the front and middle part of the concentrated release of fruit acid. for example, the three-stage powder-to-water ratio commonly used in the street, 15g powder and 1:15 powder ratio, you might as well try to adopt the water distribution of "30ml, 130ml, 65ml", and then inject it around with large water flow.


Front Street Cafe

No. 10 Baoqian street, Yandun road, Dongshankou, Yuexiu district, Guangzhou, Guangdong province