What Does High Concentration, Low Extraction Mean in Pour-Over Coffee? The Impact of Drip Coffee Water-to-Coffee Ratio on Flavor

Here it comes! Today FrontStreet Coffee is here to share with you a brewing method concept—high concentration, low extraction. This brewing method can minimize coffee's bitterness and achieve excellent flavor performance.

What is High Concentration, Low Extraction?

FrontStreet Coffee will briefly introduce this concept. Everything starts with "Golden Cup Extraction." The Golden Cup is a range determined by a group of experts through research, finding that coffee tastes best when the extraction rate is between 18-22% and concentration is between 1.15-1.35%. This data was based on American taste preferences, and people from other regions may not necessarily agree. For example, Norwegians believe coffee with a concentration of 1.3-1.55% better suits their palate. However, most people generally agree on the 18-22% extraction rate for coffee.

The concept of high concentration, low extraction refers to an extraction goal within this Golden Cup range, meaning achieving a lower extraction rate and higher concentration within this interval. For example, brewed coffee with a concentration of 1.35% and an extraction rate of 18% qualifies as high concentration, low extraction. Sometimes the extracted coffee might not fall within this exact range but is close enough to be considered high concentration, low extraction, such as coffee with 1.4% concentration and 17.4% extraction rate.

FrontStreet Coffee would like to review how concentration and extraction rate affect coffee flavor. Let's start with concentration, which is easier to understand. For example, when we drink salt water in the morning, if it's too dilute, you'll find it tasteless; if it's too concentrated, it becomes salty and bitter. The same principle applies to coffee. We don't want to drink coffee that tastes like water, but if it's too concentrated, the flavors become intense, harsh, and bitter. Within a reasonable range, for instance, coffee with 1.35% concentration will feel fuller and richer than coffee with 1.05% concentration.

The extraction rate directly affects coffee's sour, sweet, and bitter flavors. When the extraction rate is below 18%, sharp acidity and a hollow feeling are likely to occur; when the extraction rate exceeds 22%, burnt bitterness and off-flavors are highly probable. Within the reasonable range of 18-22%, lower extraction rates tend toward acidity, while higher extraction rates lean toward sweetness and bitterness.

Therefore, the high concentration, low extraction brewing method can easily produce a cup of coffee with less bitterness and excellent flavor and mouthfeel.

How to Achieve High Concentration, Low Extraction?

High concentration, low extraction is not a fixed set of brewing parameters or techniques—it's a concept, a result.

There are many ways to achieve high concentration, low extraction. For example, by reducing water volume or increasing coffee grounds to adjust the coffee-to-water ratio. If you originally used a 1:15 ratio, changing it to 1:13 will make the coffee tend toward higher concentration and lower extraction rate.

For example, Japan's famous Matsuya-style brewing uses approximately a 1:5 coffee-to-liquid ratio to extract high concentration, low extraction coffee liquid, which is then diluted to the appropriate concentration according to customer preferences when served.

Another method is to redesign an entire brewing scheme. In fact, the brewing parameters that FrontStreet Coffee usually shares are also a form of high concentration, low extraction. FrontStreet Coffee's typical brewing method is as follows:

Coffee grounds: 15g
Coffee-to-water ratio: 1:15
Grind size: 80% pass-through rate on #20 sieve
Water temperature: 91°C
Pouring method: Three-stage pour

With these parameters, light-roast coffee achieves an extraction rate of 17.8-19.5% and a concentration between 1.28-1.42%. The coffee exhibits fuller, richer flavors with bright acidity.

This brewing parameter is relatively safe and unlikely to produce bitter flavors. If you find it too concentrated, adjustment is simple—just change the coffee-to-water ratio to 1:16.

In reality, high concentration, low extraction also has negative effects. It's not perfect—while it rarely produces bitterness and maintains good flavor and acidity, the high concentration, low extraction approach also shortens the coffee's aftertaste. Therefore, for some coffee beans that exhibit excellent aftertaste characteristics, you should avoid using this brewing method.

Which Coffee Beans Are Suitable for This Brewing Method?

The high concentration, low extraction concept can be applied to medium-dark roasted coffee beans and anaerobic processed coffee beans. This is because these coffee beans have a looser texture, allowing coffee substances to release more quickly. The high concentration, low extraction approach can effectively avoid the emergence of unpleasant bitterness in coffee.

Take FrontStreet Coffee's favorite Golden Mandheling coffee as an example. It's a classic representative of dark roast. This roasting degree makes the internal structure of the coffee beans looser—lightly crushing them with your fingers can break them, indicating the coffee bean structure has been significantly altered. After grinding, they have strong water absorption. To avoid over-extraction after the coffee grounds absorb water and release large amounts of bitter substances, FrontStreet Coffee uses a coarser grind than for light-roast coffee beans. Here, a medium-coarse grind is used (70% pass-through rate on Chinese standard #20 sieve), with store EK43s setting at 11.

Roasting promotes caramelization and Maillard reactions in coffee beans. As the roast level deepens, the non-enzymatic browning caused by the interaction and decomposition of monosaccharides and amino acids under heating increases, making it easier to release large molecular substances that create burnt bitterness. To avoid extracting too many off-flavors, FrontStreet Coffee reduces the water temperature slightly. The brewing water temperature for light-roast coffee is 91-93°C, while FrontStreet Coffee recommends 87-88°C for dark-roast coffee beans.

For coffee with rich body characteristics like Indonesian Mandheling, Brazilian Queen's Manor, and Jamaican Blue Mountain, FrontStreet Coffee's baristas prioritize using KONO drippers for brewing.

FrontStreet Coffee's baristas consistently use a three-stage pouring method, which better expresses the rich body and caramel sweetness of Golden Mandheling coffee while providing higher controllability over time and water volume.

Wetting the KONO dripper allows the filter paper to fit more snugly with the coffee dripper. After pouring out the water from the share pot, add 15g of ground coffee and bloom with 30g of water for 30 seconds. This initial pour completely wets the coffee grounds for degassing, facilitating better extraction of flavor substances in subsequent steps.

Some friends extend the bloom time to 45 or 50 seconds when brewing light-roast coffee beans to enhance the initial aroma. However, for dark-roast Mandheling coffee, overly long bloom times can easily release excessive woody flavors and off-notes. Therefore, FrontStreet Coffee chooses a 30-second bloom.

For the second stage, begin pouring hot water slowly in small circular motions from the center until reaching 125g, then pause. The water flow needs to remain steady throughout. Excessive stirring can easily break apart the coffee grounds wall, leading to uneven extraction.

Wait until the coffee grounds layer drops to halfway down the dripper, exposing the coffee bed, then begin the third pour using the same technique until reaching 225g. Once all dripping is complete, remove the dripper. The extraction time is two minutes, with a 10-second margin for variation.

Finally, swirl the coffee liquid in the bottom server to mix thoroughly before enjoying your hand-poured Golden Mandheling black coffee. The brewed Mandheling coffee presents aromas of spices, dark chocolate, nuts, caramel, and pine, with a rich yet clean mouthfeel, noticeable sweetness, and a persistent aftertaste.

Important Notice :

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FrontStreet Coffee Address: 315,Donghua East Road,GuangZhou

Tel:020 38364473