For many people, coffee is a daily ritual. But behind a good cup of brew lies a series of variables that shape its flavor—from the origin of the beans, to the roasting method, to one of the most crucial factors: the grind. While at first glance it might seem like a simple matter of "fine or coarse," the differences are vast, and their impact on flavor is fundamental.

What is grinding degree?

The grind size determines how finely or coarsely the coffee beans are ground. It can be compared to granulation – from very fine dust resembling flour (espresso, cezve) to coarse particles resembling sea salt ( cold brew, French press). Each brewing method requires a different grind size because the contact time between the water and the coffee (i.e., extraction) must be adjusted accordingly to the particle size.

Extraction – the key to taste

Extraction is a process in which hot water dissolves the chemical compounds present in ground coffee beans. These compounds—acids, sugars, oils, and bitter substances—are responsible for the brew's flavor and aroma. The fineness of the grind affects the surface area in contact with the water: the finer the grind, the greater the surface area, and therefore the faster and more intense the extraction.

Too fine = overextraction

When coffee is ground too finely for a given brewing method, the water "pulls" too many compounds from it. Such a brew will often have an overly bitter, astringent flavor, lacking natural sweetness and balance. Typical symptoms of overextraction include an ashy aftertaste, tannins, and a dry mouth. Finely ground coffee performs well in pressure coffee machines (espresso machines) , where the extraction time is very short – approximately 25–30 seconds.

Too thick = underextraction

On the other hand , too coarse a grind leads to underextraction – the water doesn't have time to dissolve enough flavor compounds. Such a brew is often acidic, thin, "green," or even watery. Underextraction can also result in the dominance of unpleasantly herbal or papery notes. Coarser grinds work best with methods that require longer brewing times, such as French press (4 minutes) or cold brew (up to 12–24 hours).

Perfect balance

The optimal grind allows the beans to fully express their flavor—balanced sweetness, subtle acidity, and pleasant bitterness. Importantly, even small changes in grind (e.g., a half-degree change on a burr grinder) can dramatically alter the flavor of a cup. Therefore, professional baristas adjust their grind daily to suit the conditions: the type of coffee, the room temperature, and even the humidity.

Filter coffee – the most sensitive

When using pour-over methods (drip, Chemex, AeroPress) , choosing the right grind is especially important. Too fine a grind can clog the filter and slow down the water flow, resulting in overbrewing and excessive bitterness. Too coarse a grind can result in too fast a flow and insufficient extraction. In practice, this means that even with excellent beans, the wrong grind can completely ruin the final result.

Grinder – the most important tool for a coffee lover

While an espresso machine or drip jug can be expensive, the most important investment for every coffee lover should be a high-quality burr grinder . Only a burr grinder ensures uniform granulation, which directly impacts extraction. Blade grinders grind the beans unevenly, resulting in some particles being overextracted while others are under-brewed.

Experiment – ​​and write down

To better understand the impact of grind on flavor, it's worth keeping a brewing journal: record the grind size, extraction time, ratios, water temperature, and your taste sensations. This will help you quickly recognize the correlations and learn to control the flavor of your cup with great precision.

Grinding is one of the most important tools in the hands of every coffee lover. It directly influences the flavors and aromas found in our cup. Mastering this variable allows us to extract the full potential of the beans – and turn daily coffee brewing into a conscious, satisfying ritual.