What can occur if tamping and distribution of coffee are done poorly?

When tamping and distribution of coffee are performed poorly, one significant consequence is an increased chance of channeling. Channeling occurs when water finds paths of least resistance as it flows through the coffee puck, leading to uneven extraction. This uneven saturation can cause certain areas of the coffee to be over-extracted while others remain under-extracted.

If the coffee grounds are not evenly distributed and tamped with consistent pressure, it creates gaps and inconsistencies in the puck. As water flows through these areas, it will travel more quickly through the less dense portions, avoiding the denser areas where the coffee is tamped more firmly. This results in an imbalanced extraction process, ultimately affecting the overall flavor and quality of the brewed coffee.

In contrast, a well-tamped and evenly distributed coffee puck allows for a uniform flow of water, promoting balanced extraction, which enhances the final flavor profile and overall quality of the espresso.