As a coffee shop owner, I get asked about caffeine a lot. How much caffeine is there in coffee? Whether a light roast or a dark roast coffee has more caffeine? How much caffeine is there in cold brew coffee? How does coffee compare to teas and sodas?
To answer the question let’s talk about the two main types of commercially grown coffee beans – Robusta and Arabica. Robusta coffee comes from Coffea canephora plant. Robusta can have more than twice the amount of caffeine than Arabica. But too much of a good thing is rarely real or the best - caffeine is a bitter tasting compound. Robusta is used primarily in instant coffee and as a filler in ground coffee blends. Arabica Coffee is from Coffea arabica plant. Arabica is used by specialty coffee shops due to its more nuanced flavors and smoother taste.
At Sip Java, all I serve is Arabica, but I lack a clear measurement on the amount of caffeine that is in each of the different roasts. So, I have compiled this information from a few reliable resources. I would love to test the coffee myself but caffeine testing requires a UV spectroscopy. The Laboratory People explain step by step How To Measure Caffeine Content In Drinks. Good luck!
How Much Caffeine is there in Coffee?
Light Roast vs. Dark Roast
Which has more caffeine – dark roast or light roast? Well, the answer is nuanced, it’s a volume vs. weight question – a true bean counting exercise. Coffee beans expel water during roasting. A lighter roast will retain more water and be heavier. Darker roasts are lighter having expelled more water. As a compound, caffeine remains stable during the roasting process - meaning a darker roast doesn’t lose its caffeine. At the coffee shop, we do everything by weight. When weighing out coffee for brewing, a darker roast will require us to use a larger quantity of beans, a lighter roast fewer beans. The reasoning goes, the more individual coffee beans the greater the caffeine content. So, a darker roast should have more caffeine but its very close in terms of bean count. To brew a great dark roast coffee, we don’t need very much coffee by weight. In fact, by weight I use slightly more of the light roast to achieve the flavor profile I prefer.
Getting a definitive answer on the caffeine in cold brew is not straight forward. At our shop, cold brew coffee is steeped for 24 hours using the Toddy method, then diluted with water. Based on my research I estimate that an ounce of cold brew coffee has between 26mg to 33mg. We sell our cold brew in 16- and 20-ounce cups with ice – so approximately 338mg in 16 ounces assuming 3oz of ice.
How does coffee compare to other caffeinated beverages? The amount of caffeine in tea varies base on the variety and the how long its steeped.
Sources used in preparing this post: