The mathematical formula for making a good espresso

An international team of mathematicians and physicists proposes a mathematical model to obtain an espresso recipe with maximum extraction: 15 grams of relatively coarse ground coffee for a 40 gram drink. 

According to a report published in Matter magazine, these scientists confirm that when it comes to espresso, raw material is being wasted and the beans are ground too finely. What’s more, no two coffees are ever the same. They also argue that with fewer beans and coarser grinds than usual the espresso is just as strong but cheaper and more uniform. “It may seem counter-intuitive, but experiments and models suggest that short coffees can be made with fewer, more coarsely ground coffee beans”,  says one of the authors, Christopher Hendon, a computational chemist at the University of Oregon (United States).

"Actually, our suggestion is more of a concept than a recipe”, says Hendon, who is encouraging the industry to experiment: “You have to find the coffee grind setting that allows the water to come into contact with the dry coffee evenly. Then you have to adjust the amount of coffee or water to get the desired flavour profile, be able to reproduce the results and reduce waste”.