Does the flow rate of water injection have an effect on the flavor of hand-brewed coffee? how much water is suitable for brewing coffee?

When you are making coffee, have you ever struggled with the question of how to inject water and how much water to use? A friend asked Qianjie, "if only the rate of water injection has changed, and other parameters are the same, what is the change in the concentration and flavor of the coffee liquid?"

So this time, according to this friend's request, do a comparative experiment, according to this friend's description, "only the second stage of water injection has changed, the first one uses a flow rate of 3 grams per second, and the second uses 6 grams of water per second." the speed of water injection through the front street is about 4-5 grams per second.

The usual cooking method in Qianjie is divided into three stages of water injection, so different flow rates are used in the second stage of water injection according to the requirements, and the same water injection rate is used in the steaming stage and the third stage of water injection. This time, the Ethiopian Huakui coffee beans will be used for the experiment. The brewing parameters are as follows: powder amount: 15g grindness: screen 20 pass rate 80%: water temperature at 1:16: 91 degrees Celsius filter cup: V60 first rate: first steaming stage, the front street uses the flow rate of 4ml/s to inject 30ml water, steaming for 30 seconds. In the second stage, 120ml is injected at the rate of 3ml/s, and the time node at the end of water injection is 1 minute and 10 seconds; when the water level drops, 90ml is injected into the third stage at a rate of about 4.5ml/s, and the end of water injection is 1 minute and 50 seconds. The extraction time to be completed by drip filtration of coffee liquid is 2 minutes and 33 seconds.

The second rate: the first steaming stage, the front street using the flow rate of 4ml/s to inject 30ml water, steaming for 30 seconds. In the second stage, the rate of 6ml/s is used to inject 120ml, and the time node at the end of water injection is 50 seconds; when the water level drops, the third stage starts to inject 90ml at a rate of about 4.5ml/s, and the end of water injection is 1 minute and 28 seconds. The extraction time to be completed by drip filtration of coffee liquid is 2 minutes and 10 seconds.

In order to reduce the error of the test, Qianjie was brewed twice in each method, and the concentration of the first small flow water injection was 1.39% and 1.41%, respectively. The extraction rates are 20.58% and 20.88%, respectively. The concentration of the second large flow is 1.32% and 1.36%, respectively. The extraction rates are 19.53% and 20.13%, respectively.

First of all, let's talk about the extraction process. As the friend who asked the question said, the change of water injection rate directly leads to the change of extraction time, only changing the water injection rate of the second stage 120ml. The difference between 3ml/s and 6ml/s results in a total time difference of about 20 seconds. From the final result of the powder layer, the height of the powder wall of the two punching methods is the same, but the first method does not raise the height to the last height during the small flow injection in the second section, but in the last section of water injection, because the flow is larger than the original, so that the powder layer is raised to the height of the final result.

In the second method, the height of the powder layer of the last two water injections is the same. Qianjie can't prove which is better and which is defective. In the end, it depends on whether the configuration of other parameters is reasonable.

From the concentration data, in fact, the difference between the two data is not big, but the small flow of water injection can indeed extract more substances, which is actually related to the extraction time. If the whole process is injected with water at the speed of 3ml/s, the coffee powder layer will not be raised too high. increasing the time of water injection not only prolongs the launching speed, but also increases the extraction rate. It should be noted, however, that a high extraction rate is not necessarily a good thing. In terms of flavor, both of them are in line with the flavor characteristics of Huakui coffee and do not have any uncomfortable negative flavor. The biggest difference between the two lies in the sweet and sour feeling, the sweet feeling of berries shown by small flow water injection is more obvious, the acid quality of large flow water injection is more active, and the sense of hierarchy is more abundant. On the other hand, there is not much change in the taste of the two. Finally, the rate of water flow will certainly affect the flavor of the coffee, as in the front street experiment, there will be differences, but if the parameters are set properly, the coffee brewed out of the coffee with the great difference between the two is still in a reasonable situation. So, don't worry too much about how much the parameter of water flow can have on cooking. If it doesn't taste good, it may be that your water flow is wrong, but it's more likely that your parameters don't fit well!