In her research paper Correlation Between Caffeine and Roast Levels Using HPLC, Han reveals her findings from her thorough research on the matter. An initial discovery made was that the roasting process had no effect on caffeine content in the bean itself. This changes, however, once the coffee is brewed.
Although the caffeine content in the bean itself remains the same, differences in how coffees roasted at different levels extract when brewing do actually result in varying levels of caffeine that make it into the cup. Han found that when coffee is portioned out volumetrically (by a scoop), a cup of dark roast coffee will have around 9% more caffeine than a light roast. And when using a scale to measure the coffee by weight, she found that a cup of dark roast will have around 32% more caffeine!
All of this said, if light roasts make you feel more jittery and amped up than dark roasts – that’s valid too! Likewise, if you can’t tell much of a difference either way. Our bodies react to all kinds of things differently, and caffeine is no different. Luckily, wherever your roast preferences fall – based on caffeine, flavor, or whatever else – Schuil has plenty of options across the spectrum of roast levels, as well as some great decaf coffees, too.
BONUS: now through March 31st, receive 20% off all* coffee and tea when you spend $50 or more!