Scientists Discover How To Make The Perfect Cup Of Coffee (For Cheaper)

When it comes to coffee, you don't have to be a connoisseur to know that not all brews are created equal. We know that different blends can provide distinct flavor profiles, but sometimes even two shots of the same espresso can taste totally different. 

A team of researchers at the University of Portsmouth found there is, in fact, a way to brew a perfect espresso the same way, every single time1. Not only does this perfect brew taste stronger and more flavorful, but it also is cheaper to make and creates less waste. Us coffee snobs have our tumblers at the ready. 

Here's how you typically make an espresso: Hot, high-pressure water is forced through a bed of roasted coffee, which then transforms into that piping hot elixir we love. But espresso, in particular, is super susceptible to variation—the littlest tweak in the process can change the flavor profile completely. 

Baristas around the globe have conventionally agreed that the finer you grind the beans, the stronger the coffee. It makes sense, as finer grounds means a greater ratio of coffee beans to water, which should yield a stronger coffee. But, as researchers found, it's actually the opposite that gets you the stronger cup of joe. Here's what they found:

"When beans were ground finely, the particles were so small that in some regions of the bed they clogged up the space where the water should be flowing," says researcher Jamie Foster, Ph.D. "These clogged sections of the bed are wasted because the water cannot flow through them and access that tasty coffee that you want in your cup. If we grind a bit coarser, we can access the whole bed and have a more efficient extraction."

What he means is that when fewer beans are ground more coarsely, that high-pressure water can easily flow through the blend and yield a smoother, stronger brew. When the beans are too fine, the space between them is so small that the water has a harder time flowing through. 

"We realized that as well as making coffee shots that stayed reliably the same, we were using less coffee," Foster explains in a news release. "It's cheaper because when the grind setting is changed, we can use fewer beans and be kinder to the environment."

The team has already implemented this process in a small U.S. coffee shop for one year (they didn't specify the shop location), which reported saving thousands of dollars on coffee beans alone. Researchers estimate that if the entire U.S. coffee market were to implement this new process, they could save over $1.1 billion per year. 

In short, this new way to brew is more consistent, tastes better, and uses fewer beans—leading to cheaper costs for coffee shops and less waste. As coffee-producing countries face rising challenges to meet the demands of consumer preferences and a changing climate, this new process could help decrease the production costs of coffee while actually maximizing the quality and flavor.