Mathematicians Have Figured Out Perfect Way to Brew Coffee

Science has already bestowed on us the correct way to store our coffee beans (TL;DR— freeze them) and how we should be holding our mug, but what about the best way to actually brew the stuff?

Fear not: a group of researchers from the Mathematics Applications Consortium have saved the caffeinated day once again.

The study, which was published in the SIAM Journal of Applied Mathematics, reveals the formula needed to make the ultimate cup of joe. But there's a slight catch—it only applies if you're using a drip filter.

That Nescafé instant was never gonna cut it anyway.

Mathematicians from the University of Limerick and the University of Portsmouth looked at the factors that affect how much coffee is extracted from the grains when hot water is poured over the top and through the filter paper into a mug.

Assuming a constant temperature, they found that grain size and the rate of water flow were the the biggest influencers on how bitter the finished coffee tasted. For example, when water flowed more quickly through larger grains, the outcome was more watery because the water spent less time in contact with the coffee, therefore extraction was low.

From their observations, the math bods were then able to come up with a formula that calculated what the end cup of coffee would taste like, depending on how big or small the grains and how fast or slow the flow of water.

Dr William Lee, co-author and head of the industrial mathematics group at the University of Portsmouth, explained in a press release how the team's approach differed to other studies.

He said: "[The study] not only explains qualitatively why grind size [and water flow] play such important roles in determining the taste of coffee but also quantifies that relationship through formulas. These formulas could allow fine tuning the design of a coffee machine."

But the math geeks aren't stopping there. Lee told BBC News that studying how the coffee grains move when water is poured in could form their next study: "The shape of the coffee bed is deformed as you brew the coffee. When it goes in first, it's sitting flat at the bottom of the filter, but at the end of [brewing] it's coating the walls of the filter. This also seems to play a role in how the coffee tastes."

He continued: "Do you put [the water] in as a single jet down the centre, like water pouring out of a tap? Or do you use something more like a shower head, where it's dripping down from lots of places. Those would have different effects in disturbing the coffee bed."

The quest for the ultimate brew continues.