Scientists using complex mathematical calculations have come a step closer to understanding how to prepare a perfect cup of coffee — one of the most widely consumed drinks in the world.
Researchers have shed light on the processes governing how coffee is extracted from grains in a filter machine which could help people optimise their cuppa by applying a more precise approach.
Coffee is one of the most widely consumed drinks in the world and is composed of over 1,800 chemical components. The number of cups drunk each day around the world is estimated at over two billion.
Brewing the perfect cup of coffee is always going to be a subjective endeavour.
However, the research by Kevin Moroney at the University of Limerick in Ireland, William Lee at the University of Portsmouth in the UK and colleagues offers a better understanding of the parameters that influence the final product.
Previous research has looked at the maths of coffee extraction, but there has not been much work on drip filter machines, which make up more than half of the coffee machines sold every year in Europe.
These machines involve pouring hot water over a bed of coffee grounds housed in a filter. Gravity pulls the water through the filter, extracting soluble compounds from the coffee grains during the flow, ‘BBC News’ reported.
“Our overall idea is to have a complete mathematical model of coffee brewing that you could use to design coffee machines, rather like we use a theory of fluid and solid mechanics to design racing cars,” Lee said.
“We looked at the effect of coffee grain size on the way that coffee comes out of a filter coffee machine.
“The really surprising thing to us is that there are really two processes by which coffee is extracted from grains.
There is a very quick process by which coffee’s extracted from the surface of the grains. And then there’s a slower tail—off where coffee comes out of the interior of the grains,” he said.