The difference between extraction rate and concentration of hand-brewed coffee how to make hand-ground coffee?

Buddy: "my hand-brewed coffee smells rich in aroma, but it always feels like something's wrong!" It's not uncomfortable to drink, you have all the sweet and sour feelings you should have, but you just feel something missing. "

Qianjie: do you feel that there is no sense of hierarchy and the taste of coffee is very general?

Buddy: yes!

Buddy: should there be an uncomfortable taste in high concentration?

The concentration cannot be equated with the extraction rate directly.

Many friends will equate the concentration with the extraction rate during daily cooking, but this understanding is not accurate! First of all, the extraction rate refers to the release rate of substances in the extraction process. A coffee bean is made up of 70% wood fiber and 30% soluble flavor substances, while we only need to extract 18% 22% when we extract coffee. The concentration refers to the proportion of substances dissolved in the coffee liquid, and the concentration of hand-brewed coffee is generally no more than 2%.

To put it simply, the extraction rate is how much matter the water causes the coffee particles to release, and the concentration is how many substances are dissolved in the water. Yes, you read it right! Not all the released substances can be immediately integrated into the water ~ in the brewing process of coffee, the soluble substances are released in three stages: sour substances, sweet substances and bitter substances. These substances will be divided into two categories, one is soluble volatile aromatic substances, the other is soluble flavor substances.

In the case of medium-light-medium roasted coffee beans, the sweet and sour substances released from the front and middle stages of the extraction provide the maximum concentration for the coffee, while the bitter substances extracted in the latter stage tend to dilute the concentration of the coffee extracted before and bring a mellow feeling to the coffee. An appropriate amount of bitter substances will make coffee have a certain degree of mellow feeling, while too much bitter substances (over-extraction) will bring unpleasant feelings such as bitterness and astringency to coffee. In other words, a high concentration does not necessarily make it bitter, but the coffee that has been extracted will make you feel strong.

A high concentration of coffee does not necessarily have an unpleasant taste / feeling!

Just now it was mentioned in the front street that the concentration of coffee depends to a great extent on the extraction in the front and middle segments. If we smell the coffee with rich aroma but taste somewhat general after brewing, it may be high concentration and low extraction, that is to say, you only extract the substances in the front and middle segments, and do not dilute the concentration of the substances in the latter part of the extraction and increase the thickness of alcohols, which we can call high concentration and low extraction.

The flavor of the coffee with high concentration and low extraction is very concentrated, so Qianjie simulates the brewing of Huakui 5.0 coffee beans with high concentration and low extraction. Using 15g moderately ground coffee powder, steaming for 30 seconds and extracting in the back stage to accelerate water injection, the coffee liquid of 165ml was extracted, the ratio of powder to liquid was 1:11. The smell of brewed coffee has a strong aroma of flowers and fruits, the taste is very full and rich sweet and sour berries, but there is no sense of hierarchy, from beginning to end is sweet and sour berries.

When the concentration of coffee is too high, the flavor substances will be too concentrated, and the taste buds can not clearly identify the flavor. So when there is high concentration and low extraction, you can add warm hot water to dilute it (5g each time), that is, by pass. After each addition of warm water, you need to shake evenly and pour out a little bit to judge the concentration before deciding to add it next time, until you can start to feel other flavors.

Qianjie diluted the Huakui 5.0 coffee with about 40g warm water, and finally the coffee showed a soft mixed berry aroma, full strawberry juice and black tea. However, due to the lack of proper extraction of mellow substances, the coffee after by pass does not drink very solid and tastes light and burden-free.