Physicists at the University of Pennsylvania have investigated the physics behind pour-over coffee, aiming to improve the brewing process. Their study focuses on preventing the water jet from breaking up upon impact with the grounds.
Unlike espresso, which has received most attention, the researchers used a mathematical model to analyze the pour-over brewing method. This method involves pouring hot water over coffee grounds in a filter within a funnel-shaped cone.
Channeling is a significant issue in pour-over brewing, where the water doesn’t seep uniformly through the grounds. This can lead to reduced extraction yield and lower-quality brews. The team found that controlling water flow and pressure, as well as reducing static electric charge on the coffee grounds, can significantly improve the brewing process.
Their previous research showed that using fewer coffee beans and a coarser grind with less water resulted in better brews. More recently, they discovered that adding a single squirt of water to coffee beans before grinding reduces static electric charge and prevents clumping during brewing, leading to better flow rates and reduced waste.
The study’s findings provide valuable insights for improving the pour-over brewing method, paving the way for more consistent and high-quality cups of coffee.
Source: https://arstechnica.com/science/2025/04/the-trick-to-making-great-pour-over-coffee-with-fewer-beans