I believe that you often see the words "high concentration and low extract" in the articles on the front street, or in other ** brewing sharing! But when I searched, the explanations that popped up were all directly thrown out a bunch of incomprehensible data stacked there. It's as if the brave has just entered and exited the novice village to level up, and as a result, he directly ushered in the feeling of the final boss, and he was confused!
So today, Qianjie will transform these complex theories into simple descriptions, so that friends can better understand. High concentration and low extract, what is it! What is High Concentration and Low Extract?
High concentration and low extraction It is not a set of fixed techniques or brewing parameters, it is an extraction idea, and it is also the result of extraction.
I believe that although many friends don't know what high concentration and low extraction are, they have used the brewing method developed around the idea of high concentration and low extraction, because there are many ways to extract high concentration and low extraction: the most common is to use a large amount of coffee powder and then extract a small amount of coffee liquid. 
At this time, do many friends associate it with a large amount of Japanese brewing? For example, the powder bed is like a volcanic rush like Mt. Fuji, or the Matsuya style is steamed with a "pot lid". That's right, they just use a lot of ground coffee and then use a very low powder-to-water ratio for extraction, and although the result is not much liquid, every drop of coffee is very strong! 
The reason why the idea of high concentration and low extraction is derived is that it involves concentration and extraction rate! They are a major factor in the taste of coffee!
Like the well-known Golden Cup Extraction Table, it is made by an authoritative coffee institution in the United States, which collects a large number of Americans' preferences for coffee taste**, and studies have shown that the extraction rate is 18%-22%, and the concentration is 115%-1.35%, coffee in these two ranges, is the most delicious in Americans! It is also the preference of most of us! So, what do these two words mean?
Concentration: Concentration is the best way to understand! For example, if a glass of sugar water is too high in sugar, then it will be sweet and sweet, and if it is too low in sugar, then it will only be water with a little sweetness.
It's the same for coffee, if the concentration is too high, the flavor will be too concentrated, and it will make you feel that the whole cup of coffee is very thick, cloudy, and you can't distinguish any flavor, if it's too light, it's a cup of water with coffee flavor, only in a reasonable concentration range, you can drink a cup of coffee with outstanding flavor and full taste.
Extraction rate of thin coffee: The extraction rate will directly affect the overall flavor of the coffee, when it exceeds the maximum value of the golden cup value range of 22%, then the cup of coffee will have a strong bitter taste, which is often referred to as over-extraction.
And when your extraction rate is lower than the minimum value of 18% of the gold cup, then the cup of coffee will be prone to sour, withered grass and other under-extracted flavors. Only in the right range of extraction can the resulting coffee taste be balanced!
According to the idea of Jinbei extraction, people have created many classic brewing schemes (such as 15g powder, 225ml of 92°C water, and caster sugar grinding, which are commonly used in front streets. Three-stage brewing), so that the final coffee can be in the tasting range of the Golden Cup extraction.
However, there are some coffee beans that are not tolerant to extraction (e.g., dark roasted, or anaerobic coffee beans that have been left for a long time) because they have a loose texture and can easily be over-extracted and bitter with conventional brewing. At this time, it is necessary to reduce the extraction rate by modifying the parameters to obtain coffee without bitterness (parameters that can be adjusted: water temperature, grind).
However, if the extraction rate is reduced on the original protocol, and the other parameters are not changed, it means that the concentration will also be reduced, and the resulting coffee will become water with a coffee flavor, which is obviously not acceptable to us. Therefore, it is necessary to increase the concentration while reducing the extraction rate (the places that can be adjusted are: adding powder and reducing water). High concentration, low extraction, is such a fault-tolerant method is called high concentration and low extraction!
What brews are made with high concentration and low extraction? That's too much! We reduce the conventional brewing to a certain powder-to-water ratio, which is also an extraction method with high concentration and low extraction. Not to mention unique brews like Matsuya that require a pass to dilute a very high concentration of coffee liquid.
But again, you can't have both fish and bear's paws! The low extraction rate is mainly in the front and middle stages of extraction, and it is rarely extracted to the back stage, which will naturally reduce the tail rhyme performance of the coffee! So, choose the beans and do it
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