How Does Pouring Speed During Pour-Over Coffee Brewing Affect Flavor?

In pour-over coffee brewing, beyond objective parameters like coffee grind size, water temperature, coffee-to-water ratio, and extraction time, the pouring technique also plays a significant role in determining the flavor of pour-over coffee. For example, changes in the number of pour stages, variations in water volume for each stage, alterations in pouring height, and differences in circular pouring speed all lead to varying degrees of flavor changes in the coffee.

Today, FrontStreet Coffee will explore how the speed of circular pouring affects the taste of brewed coffee, providing insights for your reference.

How Circular Pouring Speed Affects Coffee Extraction

First, let's discuss how circular pouring speed affects coffee extraction. Regarding circular motion, when pouring water, we typically move in concentric circles in one direction. This is because moving consistently in one direction prevents turbulence, allowing water to follow the direction of movement. If you pour at fixed points or alternate between clockwise and counterclockwise directions, uncontrollable turbulence occurs at the moment of direction change, affecting even extraction of the coffee grounds.

As for circular pouring, since most modern pour-over setups use conical filter cups, circular motion ensures even extraction of the coffee grounds.

The speed of circular pouring essentially determines the intensity of agitating the coffee grounds. Let me give you an example: when dissolving drink granules, if we want them to dissolve faster, we'll use a spoon to stir. The greater the stirring intensity, the faster the granules dissolve. The water stream from our kettle acts like the spoon, and the speed of our circular motion determines the stirring intensity.

FrontStreet Coffee's Comparative Experiment

Now, let's look at FrontStreet Coffee's comparative experiment using washed Yirgacheffe Kudh Dink as the demonstration bean. The brewing parameters are as follows:

• Coffee amount: 15g
• Ratio: 1:16
• Water temperature: 91°C
• Grind size: 80% through #20 sieve
• Pouring method: Three-stage pour
• Extraction time: 2 minutes 20 seconds

The comparison factor was circular pouring speed:

• Slow group: 3 seconds per circle
• Fast group: 1 second per circle

Experimental Results

For the slow group: concentration was 1.40%, extraction rate was 20.73%;

For the fast group: concentration was 1.41%, extraction rate was 20.88%. In terms of flavor comparison, both showed notes of citrus, honey, and green tea, with no significant differences in taste.

It seems that pouring speed doesn't cause major differences in coffee flavor.

Wait... For thoroughness, FrontStreet Coffee decided to test with another coffee bean, since the first experiment used high-altitude Yirgacheffe with light roast, resulting in harder coffee beans. This time, we'll use dark roast Golden Mandheling coffee beans with the following parameters:

• Coffee amount: 15g
• Ratio: 1:15
• Water temperature: 87°C
• Grind size: 70% through #20 sieve
• Pouring method: Three-stage pour
• Extraction time: 2 minutes

The comparison factor was circular pouring speed:

• Slow group: 3 seconds per circle
• Fast group: 1 second per circle

Second Experiment Results

For the slow group: concentration was 1.39%, extraction rate was 19.11%;

For the fast group: concentration was 1.45%, extraction rate was 19.95%. In terms of taste, the slow group produced a softer, more comfortable flavor, while the fast group had a more intense, rich flavor. The mouthfeel was basically the same for both.

Through these two comparative experiments, more agitation during pouring does indeed dissolve more coffee compounds, but the difference varies depending on the bean. For harder coffee beans, the stirring intensity doesn't significantly affect the final flavor profile. However, for softer coffee beans, greater stirring intensity significantly accelerates the release of coffee compounds.

Conclusion

Of course, these experimental results are based on FrontStreet Coffee's preset parameters. If the coffee grind size changes, the experimental results will also show variations. For example, with finer grinds, the impact of stirring intensity is smaller, while with coarser grinds, stirring intensity has a greater impact on coffee flavor. The same applies to other parameters.

This is precisely why when FrontStreet Coffee shares brewing methods for dark roast coffee, we always recommend gentle, slow pouring. Because fast circular stirring has greater agitation intensity, it more easily releases flavor compounds. If other parameters aren't precise enough, it's easy to extract bitterness from the coffee.

Important Notice :

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Tel:020 38364473