Scientists Found a Smarter Way to Brew Coffee — and You’ll Need Fewer Beans

As anyone who has recently visited a grocery store or local cafe can tell you, the cost of coffee beans is becoming rather painful. In February, coffee futures spiked, causing coffee beans to reach an all-time high of more than $4.30 per pound. And while there isn’t much you can do to control the global price of coffee, a new study suggests there’s a way to stretch your beans a little further while still enjoying a rich, full-bodied cup.

Physicists at the University of Pennsylvania published a new paper in the journal Physics of Fluids showing a method to brew coffee with fewer beans that is just as strong as it would be with more, simply by adjusting your pour-over technique.

“Coffee is getting harder to grow, and so, because of that, prices for coffee will likely increase in the coming years,” Arnold Mathijssen, an assistant professor in the Department of Physics & Astronomy in the School of Arts & Sciences at the University of Pennsylvania, shared with New Scientist. “The idea for this research was really to see if we could help do something by reducing the amount of coffee beans that are needed while still keeping the same amount of extraction, so that you get the same strength of coffee.”

To determine which method produces the strongest brew with the fewest beans, the team utilized various techniques and tools, including lasers and high-speed cameras, SciTechDaily explained, to capture how each method affects brewing. However, because coffee is quite dark, the team “swapped in transparent silica gel particles in a glass cone” instead of typical coffee to facilitate observation. (Though the researchers noted they did take the time to “perform experiments with real coffee grounds to measure the extraction yield of total dissolved solids.”)

Then, using that high-speed camera, they observed what occurred as the water was poured over the simulated coffee, producing what they called “miniature avalanches.” They found that the higher the water was poured from, the more it helped stir up the particles, thus improving coffee extraction.

There was also one key tool in all this: a gooseneck kettle, which created a laminar flow effect and allowed for a gentle pour-over. “If you were just to use a regular water kettle, it’s a little bit hard to control where the flow goes,” Ernest Park, a graduate researcher in the Mathijssen Lab and coauthor of the study, added. “And if the flow isn’t laminar enough, it doesn’t dig up the coffee bed as well.”

Additionally, the team says that pouring water from as high as possible is essential for achieving a strong coffee, as it agitates the particles. However, pouring from too high can introduce bubbles, which are undesirable in the brewing process.

“When you’re brewing a cup, what gets all of that coffee taste and all of the good stuff from the grounds is contact between the grounds and the water,” Margot Young, another graduate researcher in the Mathijssen Lab, and coauthor of the study, additionally told SciTechDaily. “So, the idea is to try to increase the contact between the water and the grounds overall in the pour-over.”

While this is all great intel for coffee fanatics, the team noted that their work could extend far beyond your morning cup, including assisting scientists in understanding how erosion happens behind dams and potentially improving water filtration systems.

“We can really learn something from both the chemistry and physics point of view by looking at the kitchen,” Mathijssen said in a statement. “It leads to new science where you didn’t expect it.”