The relationship between extraction rate and concentration How much coffee concentration is appropriate? What happens when coffee is too strong?

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What is the law of gold cup extraction? How to adjust the coffee extraction rate and coffee concentration? A question that baristas often misunderstand.

To understand "gold cup extraction", we must first understand the concepts of "coffee extraction rate" and "concentration".

Coffee extraction rate: the weight of dissolved coffee ingredients as a percentage of the total weight of coffee powder used.

For example, when we use 18 grams of coffee powder to brew coffee, only 2.7-4.3 grams of coffee ingredients are dissolved in water and flow into the coffee cup, while the remaining coffee powder (15.3-13.7 grams) is called coffee grounds and thrown away.

Relationship between extraction rate and Taste of Coffee

Appropriate extraction rate: 18-22%

The words "excessive extraction" and "too little extraction / insufficient extraction" often refer to the excessive or low extraction rate of coffee.

When the extraction rate is low (less than 18%): the taste of coffee is light, the flavor is insufficient, the sweetness is insufficient, and the flavor characteristics of coffee can not be shown.

When the extraction rate is on the high side (more than 22%): the coffee has a strong flavor, mixed flavor, unpleasant flavor, such as rubber, wood and so on, while the bitter taste is heavy.

How to adjust the extraction rate of coffee?

1. Adjust the degree of grinding (that is, the contact area between coffee and water)

two。 Adjust the brewing time (that is, the contact time between coffee and water)

3. Adjust the temperature of the water

Concentration: the weight of coffee ingredients as a percentage of the total liquid weight of coffee.

For example, in a cup of 200 grams of coffee, the concentration of coffee may be only 1.2-1.5%, that is, the weight of coffee in this cup is only 2.4-3 grams, while the rest of 197.6 grams of 197.6 grams of coffee is water.

The relationship between concentration and taste

Appropriate coffee concentration (black coffee, refers to brewed coffee): 1.15-1.35 (SCAA standard); 1.2-1.45 (SCAE) standard.

The concentration is too high (when the concentration of black coffee is more than 1.5%): the coffee is too strong, especially sour and bitter, and the sweetness is not enough; the flavor of good coffee is not obvious, and it is easy to be misunderstood as "over-extraction".

The concentration is too low (when the black coffee concentration is less than 1.15%): the coffee taste is too light, the sour, sweet and bitter taste are not obvious, and the coffee flavor characteristics are not obvious, which is easy to be misunderstood as "too little extraction / insufficient extraction".

How to adjust the concentration?

Adjust the ratio of powder to water (when other conditions are constant, if there is more powder and less water, the concentration will be high; if the powder is less, the concentration will be low. )

Questions that people often misunderstand

1. "this cup of coffee is so bitter and exciting that it is overextracted!"

Case 1: this cup of coffee is overextracted. (the extraction rate is over 22%)

Case 2: the extraction rate of this cup of coffee is normal (18-22%), but the concentration is too high. This will also show the characteristics of bitterness and excitement. In this case, as long as you add the right amount of water to the coffee and adjust the concentration of the coffee to normal, the taste of the coffee will change greatly and may immediately become balanced and soft. In fact, what we are adjusting is the ratio of powder to water.

Case 3: this cup of coffee is too little extracted (less than 18%), but the concentration is too high. This will also show the characteristics of bitterness and excitement. In this case, the timely addition of water to adjust the concentration of coffee, the taste characteristics of coffee will not be very balanced, there will still be insufficient sweetness.

two。 "this cup of coffee is so light that it doesn't seem to be extracted enough."

Case 1: this cup of coffee is extracted too little. (the extraction rate is less than 18%)

Case 2: the extraction rate of this cup of coffee is normal (18-22%), but the concentration is too low. In this case, the coffee may not have obvious characteristics, but it will not have a bad taste and flavor.

Case 3: this cup of coffee is overextracted (more than 22%), but the concentration is too high. In this case, the coffee will still show the characteristics of over-extraction, can drink a faint bitter taste or unpleasant miscellaneous taste.

3. "this coffee tastes bitter and is overextracted."

Case 1: it is over-extracted and the bitterness is obvious.

Case 2: too little coffee is extracted, all the sweetness is not enough, so the bitterness is more obvious.

The above situation can be summarized into two sentences:

High concentration is not necessarily over-extraction; coffee bitterness is not necessarily over-extraction.

END