What is the best brewing time for hand-brewed coffee? the reason why the hand-brewed coffee drop is too slow and the solution

The parameter of extraction time is not actively and precisely controlled for hand pulsing. It's more of a test to see if your other parameter combinations are reasonable. In other words, if you can control the extraction time so that the error is not too different, it means that the parameters you use are reasonable and the level is stable.

The effect of extraction time on coffee flavor under the premise of constant brewing parameters, there was a positive correlation between extraction time and extraction rate. When the extraction time is short, the extraction rate is low, and when the extraction time is long, the extraction rate is high. As we know, there is a range of extraction rate that is generally considered to be better, so let's frame this range at 18-22% extraction rate. Coffee below or above this range is not so good. Reflected in the extraction time, there will be a range, but this range is not unique in the data, but is framed according to the cooking parameters (scheme).

For example, the cooking parameters used in Qianjie are "shallow baking: 15 grams of powder, 1:15, 91 ℃, 80% pass rate of sieve 20, three-stage", and the extraction time should be controlled between 1 minute 50 seconds and 2 minutes 10 seconds. Of course, if the cooking parameters are changed, the optimal extraction time range will also change. For example, the extraction time using one-throw brewing will be controlled at about 1 minute and 30 seconds. Why the parameters remain the same, but the extraction time will be different. Many friends will wonder that when the parameters are all right, the extraction time should not be too different. The problem lies in the miscalculation of the degree of grinding and personal water injection habits. The parameters generally shared are powder quantity, proportion, water temperature, grinding degree, water injection mode (filter cup). Among them, the parameters such as powder quantity, proportion and water temperature can be accurately controlled. Only in the degree of grinding and the way of water injection, it is very easy to make differences. The error that is easy to appear in the grinding degree is the misjudgment caused by the poor grinding evenness. to put it simply, the coffee powder diameter of the good quality bean grinder will be more concentrated, and the overall thickness difference is small; while the coffee powder diameter of the poor quality bean grinder is relatively dispersed, and the overall thickness difference is large. Qianjie recommends the use of No. 20 sieve for calibration, which also has a pass rate of 80%. The bean grinder of poor quality produces more fine and coarse powder. in addition to the uneven extraction, it also takes a long time because of the large amount of fine powder. Qianjie met a friend for help, it is understood that he used Qianjie cooking parameters for cooking, but could not control the extraction time to less than 2 minutes 10 seconds. Qianjie observed his cooking process, and it turned out that he was used to using a very small flow of water to inject water, which made his whole time of water injection longer, and the small flow of water injection could not raise the water level, nor was it conducive to launching, and it would take longer to get into the water. In the front street, it is recommended to use the amount of water from 5ml/s for water injection. During the second stage of water injection, the liquid level is raised to the short diversion bone of V60, and the last section of water injection is just up to this height.

The extraction time is also included in the controllable parameters. Most cooking schemes use the extraction time as a passive parameter to check whether there are any accidents in the cooking parameters or in the process. But there are also cooking methods that use time as a control parameter, such as the four or six cooking methods that Mr. Guzhe shared with you. The four six flushes and one is divided into five times of water injection, and the interval of each section of water injection is a fixed 45 seconds (when the amount of powder is 20g). The advantage of this is that there is no need for the brewer to judge when the water injection can continue, but only step by step. Time is up, so the final extraction time can be well controlled.