The principle of spot-by-drop hand flushing for segmented extraction testing

It was interesting to see other people doing manual extraction. The experiment was the only criterion for testing the truth, so I came to play it once.

Coffee beans: Yega Snow Coffee Konga

Water temperature: 88 degrees

Grinding: normal hand impact size

Method: hand flushing

The first test:

Did not take a picture, drew a picture to show

Cup test results: the first two cups are sweet, sour and sweet, with fermented aromas; the last two cups are floral and citrus, with distinct layers.

After testing, the first feeling is that the moderate baking products will be easy to melt in water, while the shallow baking products are relatively difficult to melt in water.

The second test:

Test the effect of low ratio of water to powder and lengthening extraction time on segmentation.

Operation: fill it with water just enough to fill a cup, cut off the water, then rest for 60 seconds, then to the next cup, and so on until the fourth cup is finished.

That is, each cup contains water filling and steaming for 60 seconds.

Cup test results: 4 cups are sweet, sweet and sour, fermented aroma, cups 1 and 2 are the strongest, cups 3 and 4 are slightly weaker. The aroma of flowers and fruits is only a little in Cup 4.

This result is very surprised, the last two cups in the first test no longer have the taste of the first two cups, but they appear again in the second test, and the aroma of flowers and fruits is gone.

If there is no problem, it can be summed up like this.

Factors affecting extraction:

Medium baked products-lengthen extraction time

Shallow baking products-increase the ratio of water to powder (the more water, the lower the concentration, the easier the low molecular weight substances in coffee come out)

In order to verify whether it is normal, there is a third test.

The third test:

The method of operation is the same as the second test, the difference is that the large flow begins in cup 3 to increase the amount of water in the filter cup.

Cup test results: sure enough, as expected, Cup 4 showed a bright aroma of flowers and fruits.

It suddenly reminds me of the Japanese hand-punching method. Keep dripping on the dry powder for a long time and then quickly end with a large flow of water.

It may be to use a long time drip to extract the aroma of the back part of the baking as much as possible while not producing the miscellaneous smell in the environment with low water powder ratio, and then extract the flower and fruit fragrance of the front part with a high water powder ratio.