There has been much debate about the amount of caffeine in coffee. Is there more or less caffeine in a shot of espresso versus a drip, press or moka pot? And what about roast level? Urban myth suggests darker roasts have more caffeine than lighter roasts. Somewhere out there is the truth. Let’s break it down to what we know.
Each individual coffee bean contains basically the same amount of caffeine. Roasting does not affect caffeine levels. The darker the bean, the more water has been removed, so each individual bean weighs less. Alternatively, the lighter the roast, the greater the mass, each individual bean weighs more.
Now put it all together. We know roasting does not affect caffeine levels in each bean. We also know roasting reduce the mass of each bean. So - does brew method affect caffeine level?
Well, that depends on how you are measuring your beans. Are you weighing them or counting scoops? If you are measuring coffee by weight, you will get more caffeine with a darker roast, regardless of brew method. Darker roasts have less mass; therefore you need more beans to get the same weight as a light roast. More beans mean more caffeine. However, if you measure by counting scoops, you are using the same volume of coffee, and thus, there is no measurable difference in caffeine.
Use the same reasoning when comparing brew methods and caffeine levels. Do you use a greater mass of coffee when pulling an espresso shot, making drip, or doing a press coffee? Whatever brew takes the greater mass, would have the most caffeine.
However, try to keep this in perspective. There are only about 90 additional coffee beans in a pound of French roast, compared with beans roasted to a City level. That’s a minimal impact. And remember, on average, it takes about 100 beans to make a cup of coffee.
However, if you really want to throw a glitch in our reasoning, go back to my first statement - Each individual coffee bean contains basically the same amount of caffeine. Well, that’s sort of true. Arabica beans, though they typically taste better, have about half the caffeine, than Robusta beans.
So – roast level doesn’t impact caffeine levels, whereas brew method does, minimally, and ONLY if you are measuring your beans by mass. But remember, these are minute differences. If you are really bothered by the caffeine, drink decaf. And make sure it’s Swiss Water Decaf. If you need more caffeine, drink more coffee, and choose your bean varietal wisely. Just make it a brew and roast you like.