The Impact of Coffee Fines on Brewing

The grind size of coffee has a significant influence on brewing methods (such as Pour Over, V60, Chemex, etc.). Particularly important is the presence and distribution of "fines," or very small coffee particles, which substantially impact extraction efficiency, flavor balance, and the resulting coffee's texture.

What are Coffee Fines?

Fines are tiny coffee particles produced during grinding, significantly smaller than the main particle size. Although fines usually constitute a relatively small proportion of the total grind, they greatly influence extraction and final cup characteristics.

Effects of Coffee Fines on Brewing

1. Increased Extraction Rate (Faster Flavor Release)

• Fines have a larger surface area, leading to faster extraction when in contact with water.
• Excessive fines can lead to over-extraction, increasing bitterness and astringency.

2. Filter Clogging and Flow Rate

• Fines can accumulate at the bottom of the filter paper or within the coffee bed, causing blockages.
• Slower water flow extends extraction time, potentially causing uneven extraction and inconsistent flavor results.

3. Enhanced Body and Texture

• An optimal amount of fines can increase the coffee's body, creating a richer and fuller mouthfeel.
• Too many fines, however, can cause a muddy texture or gritty feeling, compromising clarity and cleanliness.

4. Flavor Inconsistency

• Inconsistent amounts of fines between brews can create significant flavor variations, even if the same recipe and brewing technique are used.

Solutions and Recommendations

🔸 Use a High-Quality Grinder

• Grinders such as Timemore Chestnut X, Comandante, and EK43 can achieve better particle uniformity, minimizing the production of fines.

🔸 Sifting Coffee Grounds

• Tools like the Kruve Sifter help remove fines, enhancing brewing consistency and flavor clarity.

🔸 Adjust Brewing Techniques

If fines are an issue, adjust the brewing parameters:

• Decrease the coffee dose slightly.
• Use slightly lower water temperatures.
• Adopt gentle, controlled pouring techniques.
• Minimize excessive agitation or stirring.

🔸 Thoroughly Rinse Filter Papers

• Proper rinsing of filters removes paper flavors and ensures smoother water flow, reducing fines-related clogging and extraction problems.

Controlling fines effectively will lead to a more consistent and satisfying coffee experience.