Why is hand-brewed coffee sour and tasteless? How can I make coffee by hand?

In the store, Qianjie will often meet coffee lovers who come to communicate, many of whom buy coffee beans to brew at home, and then come to the store to order a cup of hand-brewed coffee with the same beans, comparing the difference between the barista's brewing and his own brewing.

There are also some hand-brewed coffee lovers at home who can't come up with the flavor description on the coffee package, so they come to Qianjie to discuss which link has gone wrong. Qianjie synthesizes everyone's questions and summarizes some possible reasons. The appreciation period of coffee beans here in front of the street briefly talk about what is flavor, flavor and taste are some differences, flavor is more by aroma and taste together composed of sensory experience, let us taste like some kind of concrete flavor. This flavor is linked to the taste period of coffee beans. If you buy a bag of coffee beans, there will be a shelf life of 365 days, a taste period of 45 days, and a baking date. Shelf life means that coffee is safe to drink during this period; appreciation period means that coffee beans have a good flavor performance during this period. After this period, the flavor of coffee is not obvious, only the taste of coffee is left.

Qianjie also learned that some enthusiasts like to buy a few bags of coffee beans at once, and the frequency of cooking is not high, so that many coffee beans have exceeded the appreciation period before they have time to brew them. In this case, the coffee beans themselves have no flavor, not to mention whether they can rush out the flavor. Therefore, if you want to flush out the flavor of coffee, you must first ensure that the coffee bean itself has a rich flavor. After roasting, coffee beans need 4-7 days to grow, because the freshly roasted coffee beans have more carbon dioxide, these gases will hinder the release of coffee substances, so it is necessary to keep coffee beans for 4-7 days to let out some gas. This makes it easier to flush out the coffee flavor. The relationship between carbon dioxide and flavor substances is complementary, when carbon dioxide is discharged, some volatile aroma compounds will also be discharged with the gas. Therefore, when raising beans, the coffee flavor is the best, and then the flavor will slowly dissipate, generally lasting until the 45th day, the coffee flavor is not obvious. So if you want to flush out the rich flavor of the coffee, you must pay attention to the date of the coffee beans.

Water quality more than 98% of a cup of hand-brewed coffee is water. Therefore, water is also an important parameter that affects the flavor of coffee. In front of the street, some enthusiasts directly use boiled tap water to make coffee according to their own habits. There is a problem with tap water, that is, the content of trace elements in tap water can not be guaranteed. At present, it is generally accepted that the theories of coffee water use are as follows: 1. It is better to make coffee with TDS lower than 100ppm, and TDS higher than 200ppm is hard water, so the coffee will be extremely bitter. 2. An appropriate amount of calcium and magnesium ions are beneficial to brewing good coffee. 3. Pure water without any substance is not suitable for brewing coffee, and the coffee will show a sense of emptiness.

It doesn't matter if you don't understand. To sum up, if you want to make good coffee, you are advised not to use tap water, pure water or distilled water. Filtered water and mineral water that meet the requirements of TDS can be used. Many new lovers think that the water injection techniques and skills of hand flushing are very important; in the view of Qianjie, the right parameters are more important. Some 1-2-day paid courses that teach you how to make coffee actually tell you the standard of brewing parameters and a simple brewing plan with high fault tolerance and no extreme requirements for water injection, so that you can make better coffee than before. In fact, the reason is also very simple, many beginners will make it very difficult to make coffee, coupled with the lack of knowledge of the "right way", they will keep groping in mistakes and find out more mistakes. When someone tells you a "standard answer", you have a clear trial and error direction, so as to slowly find out what is right for you. And the "standard answer" is very simple. Reasonable amount of powder, reasonable water temperature, reasonable degree of grinding, reasonable proportion, reasonable time, reasonable way of water injection, the coffee is right. In fact, these parameters complement and influence each other. The reasonable amount of powder mainly depends on the recommended load of the filter cup, which is nothing to say. Reasonable water temperature and proportion, at present, there is also a more unified range, water temperature is generally controlled in 90-93 degrees (shallow baking), the proportion of powder to water mostly hovers between 1:15 and 1:16. As for the degree of grinding, time and the mode of water injection are a group of relationships that influence each other, it is necessary to strike a balance among the three groups. First of all, the thickness of the hand grinding degree should not be too outrageous. If the water level drops very slowly and the finished powder bed is muddy, then the grinding degree is obviously fine; if the water level drops very fast, the powder bed exposes very thick bulk particles, that is to say, the grinding degree is rough. Fine grinding will make the cooking time longer, rough grinding will make the cooking time shorter. The method of water injection will also affect the cooking time, the large flow will shorten the cooking time, the small flow will prolong the cooking time, the more separate water injection times, the longer the cooking time.

And time is the parameter to test whether the degree of grinding matches the technique. For example, the coffee that is often brewed is very light and has no flavor. In addition to the problem of the ratio of powder to water, the reason is that the brewing time is too short and the flavor of the coffee ends before it is fully released. If you are not sure whether your grinding degree is right, you can set the cooking time at 2 minutes, water injection is divided into 3 stages, and the time is exactly about 2 minutes, which means that the grinding degree and technique are all right. If the coffee beans are good, the water is good and the brewing process is reasonable, you can flush out the flavor of the coffee. Of course, if you want to pursue the ultimate flavor, you need to learn and understand it more deeply.