The art of brewing coffee has long been approached scientifically, and not it is being done so by actual scientists. In an article titled “Asymptotic Analysis of the Dominant Mechanisms in the Coffee Extraction Process” that will be published in next week’s SIAM Journal on Applied Mathematics, researchers Kevin M. Moroney, William T. Lee, Stephen B.G. O’Brien, Freek Suijver, and Johan Marra examine the science of coffee extraction and specifically how extraction works within a filter brewing system.

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According to, this new research is building upon a 2015 paper by the same authors but with the focus shifting toward filter brewing:

“Most of the models of coffee extraction we found in the literature either focused on batch extraction in a well-mixed system, or derived general transport equations without proposing specific extraction mechanisms or validating with experiments,” Moroney said. “In comparison, our model describes flow and extraction in a coffee bed, specifies extraction mechanisms in terms of the coffee grain properties, and compares the model’s performance with experiment. Our initial focus on the flow-through cylindrical brewing chamber allowed us to consider the model in one spatial coordinate and ensure that the model assumption of a static bed was valid.”

Or put more simply:

“The research work is ultimately aimed at improving our understanding of the brewing process and understanding the relation between brewing process parameters and perceived coffee taste,” Marra said.

The research breaks down the coffee brewing process into essentially two steps:

“Initially, the concentration of coffee in the bed is determined by the balance between a rapid extraction from the surfaces of coffee grains and the rate at which coffee is removed from the coffee bed by the extracting water. Later in the process, the extraction is dominated by slow diffusion of coffee from the kernels of larger grains, which was initially negligible.”

Along with grind size/surface area, the researchers look into how water flow rates and bed shape affect extraction. Their hope is to uncover the mathematics of coffee brewing in order to apply it to how coffee makers are constructed.

The article itself is pretty dense, never mind the actual work of the researchers, and it has yet to really break any new ground on what exactly is going on during extraction. But this rigorous analytical approach has promise of producing results that will have real world application for coffee brewing. Or at the very least, next time someone tells you “It’s just coffee,” you can forward them this study and reply with a smug, “Is it?”

Zac Cadwalader is the news editor at Sprudge Media Network.

*top image via Breaking Bad

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