Jolting Java

Wanna better cup of joe?

This is Sandra Tsing Loh with the Loh Down on Science.

You’ve just rushed out the door after filling your coffee tumbler and – BLECH! Why does this homebrew taste so YUCKY?

Grinding coffee beans produces static electricity. This causes clumping and a diluted taste. Is there a way to make the beans less… static-y, more tasty?

Enter Joshua Harper and team from the University of Oregon.

Researchers sourced different coffee beans based on properties like country of origin and roast color. Next they measured static charge in the coffee grinds…

Findings? Lighter roasts, coarser grinding, and beans with higher water content produced less static charge. Researchers tested if adding water to the beans before grinding could prevent charge buildup.

Surprise, it worked! Wet grinding coffee prevented clumping caused by static charge leading to more consistent tasting coffee. It was also about TEN percent more concentrated!

This knowledge can improve the all-important skill of brewing good coffee. It also helps better understand natural phenomena involving static charge.

And with that said…… I’m getting back to the grind.


Reference: Méndez Harper, J., McDonald, C. S., Rheingold, E. J., Wehn, L. C., Bumbaugh, R. E., Cope, E. J., Lindberg, L. E., Pham, J., Kim, Y.-H., Dufek, J., & Hendon, C. H. (2023). Moisture-controlled triboelectrification during coffee grinding. Matter. https://doi.org/10.1016/j.matt.2023.11.005