How to Test Whether Your Coffee Grind Size is Correct

I'm guessing that if you've clicked on this article, you're also struggling with the problem of coffee grind size.

In the realm of pour-over coffee, compared to other parameters, grind size remains one that everyone finds difficult to articulate clearly in words. Since everyone's coffee grinder equipment varies, when discussing brewing grind size with customers, many baristas first resort to visual analogies to describe it. Despite knowing this has certain limitations, it's indeed one of the fastest ways to establish a conservative brewing framework.

Therefore, learning to quickly determine which category of coarseness coffee powder belongs to is a crucial step in brewing delicious coffee. Among these, the most commonly used seasonings for comparison are fine salt, fine sugar, coarse sugar, and sea salt texture.

Fine Salt

The most characteristic feature of the fine salt analogy is "refined and fine," appearing both loose and uniform, with almost no granular feeling when rubbed. This fineness is suitable for extraction methods with pressurization functions like moka pots, where fine powder can effectively release coffee oils under high temperature and pressure.

Fine Sugar

Fine sugar coarseness is the most common analogy for pour-over grind size, feeling soft and slightly sandy to the touch, with no obvious clumping. During extraction, small particles can more fully release flavor compounds, generally suitable for light to medium roasted coffee beans that primarily express floral and fruity aromas.

Coarse Sugar

Coarse sugar, also called white sugar, isn't easily distinguishable from fine sugar by naked eye observation, but when rubbed between thumb and forefinger, you can feel obvious granular texture (and if chewed, you can hear the crunching sound). The surface area of coarse sugar is relatively larger, which helps avoid over-extraction due to excessive steeping time, making it suitable for medium-dark to dark roasted beans, such as those featuring chocolate, caramel, and cocoa flavors.

Sea Salt Texture

Sea salt texture is the easiest to identify, referring to something similar to large-grained crystallized coarse salt, with mostly visible chunks and overall unevenness. Therefore, it's more suitable for immersion brewing rather than drip brewing, paired with 2-3 minute extraction times, such as with French press or clever dripper.

If visual inspection doesn't yield results, we can also combine the particle morphology and duration during the extraction phase to determine if the grind is too coarse, too fine, or just right. Because regardless of particle size distribution, we still need to test based on the formal brewing stages and final taste. At this point, we can use the morphology of suspended particles during blooming, total drip time, and coffee ground particle size to find the answer.

Practical Grinding Test

Here, FrontStreet Coffee uses sun-dried red cherry as the brewing star, with grinding equipment being the MAVO Wizard 2.0 hand grinder, demonstrating to everyone using the methods mentioned above how to "blindly test" the ideal grind setting when facing an unfamiliar grinder.

First, use a small amount of coffee beans (3-5 grams) to test grind at the first setting. The resulting particles are mostly chunky, clearly close to sea salt texture, so we can adjust significantly finer. Here, FrontStreet Coffee turned 10 settings toward the fine grinding direction, and the resulting powder approached fine sugar size, which meets the pour-over grinding requirements. At this point, we can enter the extraction phase to verify it.

Sun-dried Red Cherry Coffee Beans: 15g
Total Water: 225g
Water Temperature: 91°C
Filter: V60
Three-Stage Pouring: 30g, 95g, 100g

During the blooming stage, the adjusted finer coffee particles are clearly tightly connected, with high water retention. As the pouring approaches the end, the flow rate becomes noticeably slower, and the filter paper is likely clogged by a large amount of very fine powder, with extraction time exceeding two and a half minutes. From the finished coffee grounds, you can see mud-like powder sticking to the surface, and the coffee tastes like heavy berry notes with a slightly astringent aftertaste. This indicates that the grind is too fine, causing over-extraction, so we need to adjust it slightly coarser. Here, FrontStreet Coffee adjusted 3 settings coarser and continued testing.

Under the same brewing parameters, the new setting's coffee powder shows larger suspended particles during blooming, with a drier slurry. The flow rate remains stable throughout the entire pouring process, with total extraction time of 2 minutes and 8 seconds. The coffee grounds are fluffy and evenly distributed on the filter cup wall, and the coffee tastes moderately concentrated, with citrus-like fruit acidity and caramel aftertaste. It seems this is the ideal grind size we've been looking for.

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FrontStreet Coffee
No. 10, Bao'an Qianjie, Yandun Road, Dongshankou, Yuexiu District, Guangzhou, Guangdong Province

Important Notice :

前街咖啡 FrontStreet Coffee has moved to new addredd:

FrontStreet Coffee Address: 315,Donghua East Road,GuangZhou

Tel:020 38364473