How to distinguish between under-extracted and over-extracted coffee? How will over-the-top coffee behave? Why is the lack of aftertaste?

Whether for Italian style or hand brewing, if you want to make a delicious cup of coffee, it is absolutely important to learn to judge the degree of coffee extraction. Because only if you know what is good and what is wrong with this cup of coffee, can you correct it accordingly and make a more delicious coffee. Although everyone's definition of good drink may be different, but for the understanding of bad taste, we must be able to reach a consensus! So once there is a problem with the extraction of coffee, then the problem will be reflected in the taste, forming a "defect". We only need to catch this defect to know what is wrong with the extraction of this cup of coffee, and then we can modify it.

That's right! First of all, a premise is that although gold cup extraction defines insufficient and excessive extraction, it is best not to judge the degree of extraction by numerical value. Because of the different quality and treatment of beans, the theory of gold cup extraction may not be accurate. The coffee in the gold cup extraction is not necessarily good, and the coffee outside the gold cup extraction is not necessarily bad, so we still have to return to the essence and take the imported coffee feeling as the basis of judgment. Well, needless to say, let's talk about the performance of underextracted coffee in front of the street.

Insufficient extraction means that hot water is not fully extracted, so the coffee eventually extracted will be due to insufficient substance content. The following situations occur: sour, sharp: sour, sweet, bitter and salty are the four flavors that we can extract from coffee. Because the four flavors are opposed to each other and restrict each other, therefore, they are all indispensable in a cup of coffee. We can think of coffee as lemon tea. In addition to the sour taste of lemon, the sweetness of fructose is also indispensable, because only by adding fructose can the high acidity of lemon be softened and the whole cup of lemon tea can be accepted by the old people. In yesterday's article, Qianjie mentioned that their four flavors will have different dissolution rates due to different molecular sizes, so they need a complete extraction, so that the four flavors each have a balance with other flavors. When we do not extract enough, the coffee will be full of a lot of sour taste, because it is the fastest dissolving rate of a flavor. When there is no check and balance of other flavors, the sour taste will be particularly prominent, sharp and uncomfortable because of its excessive quantity. On the other hand, the lack of sweetness, or the mellow feeling of bitterness, can also be a sign of inadequate extraction.

Salty taste appears, obvious: unlike fresh taste, although salty taste is weak in coffee, it is a taste that does exist. It's just that its proportion in coffee is not high, so it is difficult to detect under the cover of other flavors. When the extraction is insufficient and a lot of taste is missing, the salty taste will be revealed. It can not be said that exposure is easier to be captured by people, so the appearance of salty taste in coffee is also a manifestation of insufficient extraction.

Lack of rhyme / no: Yu Yun, Hui Gan and other performances after drinking coffee are emitted by the dissolution of coffee substances left in the mouth. When we do not extract enough, the aroma substances in the substance are greatly reduced, so the afterrhyme will not be so obvious, not so prominent, and even there will be no aftertaste at all.

Weak flavor, mediocre: insufficient extraction, simple understanding is not enough extraction, failed to fully extract the substances in the coffee, including flavor substances! And many flavor substances need different substances to form together, which is still the same as lemon tea. When the extraction is insufficient, a flavor may lack a large number of composition conditions, and there is no way to get a satisfactory experience of the flavor alone, so the flavor is not obvious and thin, which is a manifestation of insufficient extraction.

Excessive extraction is the opposite of insufficient extraction. If insufficient extraction is not enough, then excessive extraction means too much extraction, and all that should not be extracted will be extracted! So in the end, coffee will show these things: bitter! Thai bitterness: when we overcharge coffee powder, it is easy to increase the proportion of bitterness. Because we are more sensitive to bitterness, when there is too much bitterness in the coffee, it will greatly suppress the expression of other flavors, making people feel as if the whole cup of coffee is bitter!

Taste hollow, monotonous: although the presence of bitter substances can increase the alcohol thickness of coffee, but that is under the right amount of conditions. When there are too many bitter substances, the effect will be the opposite, not only the thickness of alcohol is not well reflected, but because of the overflow of bitterness, the performance of other flavors is reduced, making the coffee as a whole hollow, lack of layering, and very monotonous. Miscellaneous taste and astringent taste emerge: the overflow of bitter taste is not the only manifestation of insufficient extraction. In many cases, there is another reason why people do not want coffee to be over-extracted, which is the release of miscellaneous taste and astringent taste. Although coffee beans have 30% soluble matter, not all substances are positive! Because it contains miscellaneous flavor, astringent feeling of these unpleasant material existence. When the coffee is extracted excessively, the unpleasant miscellaneous taste and astringent feeling will stream out and combine with the bitter taste to produce a taste that is difficult to swallow.

To sum up, as long as we feel these corresponding negative situations in the taste of coffee, it shows that there is something wrong with the extraction of coffee! Of course, the extraction of some coffee may not be satisfied with all the conditions in one direction, such as the channel effect of espresso. A pressed powder will have the taste of underextraction and over-extraction in a cup of espresso because of the uneven distribution of hot water. This is the condition of uneven extraction. When there is a negative situation in the extraction of coffee, then we need to make some adjustments to the next extraction, improve the extraction or reduce the demand. Italian hand flushing is all the same! After all, in the final analysis, although there are different extraction methods, they are all the same in theory! It is said that the line is like a mountain, but you should know that the line is not separated.

-END-