What is the reason for over-extracted coffee? What are the extraction parameters of hand flushing? How do water temperature and grinding degree affect brewing?

Surprise question: what is the most important thing to guard against when making coffee?

That's right! It's superb! Because the excellent coffee always has some unpleasant taste or feeling, these existence will make people resist this cup of coffee and make it difficult to swallow. Therefore, when we are making coffee, the most important thing to avoid is over-extraction! Miscellaneous, scorched, bitter and astringent are all the flavors that often appear when coffee is too extractive. Because the negative effects of over-extraction are so many that it makes people more sensitive, and then it makes people think that all the discomfort comes from over-extraction. But in fact, not all negative bitterness comes from excellence.

For example, when the coffee is too strong, the coffee will form a bitter taste because the flavor is too concentrated. Then the taste like this is not superb! So some friends asked, what kind of coffee would be superb? There are two main definitions of over-extraction. Let's first talk about the original definition of over-extraction: it comes from the concept of gold cup extraction.

The concept of golden cup extraction expresses that the extraction rate (and concentration) of coffee has a most popular range, as long as we control the extraction rate of coffee at 18%-22%, then the taste of this cup of coffee is acceptable to most people. Because it's hard to have a negative taste at this time. When the extraction rate is more than 22%, coffee is easy to produce some offensive taste! Therefore, when the extraction rate of coffee exceeds 22%, it will be defined as over-extraction. But it turns out that not all coffee with an extraction rate of more than 22% has an objectionable negative taste. This mainly has a lot to do with the substance content in coffee. Therefore, what we now think of as over-extraction is that it is defined as over-extraction when there is a bitter, astringent, miscellaneous taste in the coffee, rather than relying on the extraction rate. It is perfectly normal if the phenomenon of over-excellence occurs occasionally. Because the temperature and humidity of the environment are constantly changing, and the state of the coffee bean itself is also changing. So we can't guarantee that the same parameter can be applied to all coffee beans. But if over-extraction occurs frequently, it means that there is a big problem with your extraction.

The reason for over-extraction is very simple. The extraction efficiency of one or all of the parameters is too high, so some bad substances in coffee are extracted. To put it simply, the cooking plan is unreasonable, or the fault tolerance rate is too low. Because many friends will use some extreme extraction methods in order to pursue the ultimate flavor display, although these extraction methods can bring you quite cracked flavor performance, but at the same time, the over-extraction probability of coffee is also very high. It is the so-called high risk and high return ~ therefore, if we want to reduce the occurrence of over-extraction, we need to reduce those unreasonable and high extraction efficiency. In the parameters of hand-brewed coffee, we can subdivide the following conditions: too high water temperature, too fine grinding, too long time, too much water, or too many times of mixing, too strong. If you don't know how to adjust, you can skip to this article to explain "cooking logic" in detail.

In addition, the quality of the bean grinder is also worth exploring. When the grinding uniformity of the bean grinder is too low, it will produce a lot of very fine powder, which is not only easy to extract, but also easy to cause blockage, along with other coffee powder of normal size. Therefore, the uniformity of coffee powder will also be an object to be studied.

-END-