Less coffee and less finely ground, prepared with less water: this is the 'recipe' for having the best espresso, which at the same time allows you to save money and use less for the same taste. The formula, published in Matter magazine, was not developed by a bartender, but by a group of 10 chemists and mathematicians from five countries, led by Jamie Foster of the British university of Portsmouth.
The starting point of the study is that, even if made in the same way, espresso cups often have a different taste from each other. So, after analyzing several variables, such as the size of the grains, the water pressure, the output flow, the quantity of coffee and the extraction energy, they found the mathematical model that allows to reduce by 25 % the quantity of coffee used to prepare a good espresso in each cup and save 13 cents per cup for stores in the United States only.
"Our method allows you to push on extraction and have a coffee with an excellent flavor, more sustainable and cheap", comments Christopher H. Hendon, one of the authors of the study. The formula found foresees to use 15 grams of coffee instead of 20, and to grind the grains more roughly, in order to obtain a cup of espresso more quickly (instead of 25 seconds, it takes from 7 to 14) but equally with an enveloping aroma. "A good espresso can be made in many ways - Hendon concludes - but with this study we give a map to have one that has the same flavor even 100 times in a row". The last word is now up to coffee lovers