Science takes a shot at your afternoon pick-me-up

Perfecting pour-over coffee Coffee is a ubiquitous pick-me-up, but climate change is making Arabica coffee plants—which are temperature sensitive—more challenging to grow. And that means coffee could become a liquid luxury. Physicists at the University of Pennsylvania wondered if they could use science to get more out of pour-over coffee. “The main idea is whether it might be possible to use those coffee beans just a little bit more efficiently so that you can still get the same strength or the same extraction but maybe using slightly fewer beans,” says Arnold J. T. M. Mathijssen , who led the group. The pour-over method for making coffee involves streaming hot water over coffee grounds in a cone-shaped filter that sits within a funnel and collecting the extraction liquid. Chemists will recognize the process as gravity filtration , and some pour-over equipment even uses chem-lab aesthetics reminiscent of scientific glassware. Mathijssen and