Secret to stronger pour-over coffee with no extra beans unlocked by scientists

Pouring water slowly, steadily and from height is key to achieving avalanche' mixing effect

Forget expensive beans and pricey filters - if you want a stronger cup of pour-over coffee, just add water slowly, steadily and from a height, researchers say.

While there are myriad ways to make coffee - from moka pots to cafetieres and barista-style machines - pour-over coffee is an everyday staple for many. Now scientists say they have discovered how to make a stronger cup using the same quantity of ground coffee.