Let's Talk About Caffeine: The Many Misconceptions Surrounding Coffee's Trademark Energy Booster
The morning pick-me-up. Go-juice. Rocket fuel. The daily fix. When people talk about their coffee like this, they’re really talking about coffee’s most well-known addition: caffeine. Behind coffee’s trademark energy boost is this little stimulant. Caffeine is what gives you that little kick in the morning and what keeps you up at night. It’s also perhaps a little misunderstood.
Let Mighty Beast set the record straight.
Light Roast Versus Dark Roast
One of the most common coffee myths is that dark roast coffee has more caffeine than light roasts. Or that light roasts have more caffeine than dark roasts. But which is correct? Neither? Both?
Yes.
Dark roast tastes stronger, so it must hit harder, right? Actually, no. The difference in the amount of caffeine between a light and dark roast is very small. What does change a lot is flavor. Dark roasts are known for bold, smoky flavors that taste stronger, but that doesn’t equal more caffeine.
Light roasts, on the other hand, don’t have significantly more caffeine either. Some will tell you that your coffee loses caffeine the longer you roast it. That does make logical sense. But caffeine is actually pretty stable during the roasting process, so most of it survives whether the beans are roasted lightly or taken all the way to dark.
Most coffee roasting happens roughly in the range of 180–240°C. Hot, sure, but not quite hot enough to lose a significant amount of caffeine. Those compounds start to break down between 230–285°C. You will lose some caffeine the darker you go, but probably not enough to notice.
Weigh This. Measure That.
Things start to get a little tricky when you measure your coffee. Dark roast beans are less dense because they’ve been roasted longer. Beans will puff up as they roast and lose water content. If you scoop coffee by volume (like using a tablespoon), light roast beans are denser and you’ll actually get slightly more caffeine in that scoop. But if you weigh your coffee, the caffeine difference between light and dark roast will be roughly the same. So depending on how you dish it, you might get a little more.
Arabica vs. Robusta Beans
We’ve talked about how roasting doesn’t affect caffeine significantly. And we’ve talked about measuring. But what about the beans themselves?
From our Ethiopia Yirgacheffe and Brazil to our dark La Brea, different Mighty Beast beans will have different levels of caffeine. That said, these three are all Arabica beans. Known for growing in higher altitudes, having more complex flavors, and being larger in size, Arabica beans are what you mostly see in specialty coffee (including ours). The other main variety of coffee bean is called Robusta.
Robusta beans have almost twice the amount of caffeine as Arabica. Typically, they grow at lower altitudes and are known for earthier flavors. And due to their high caffeine content, they are especially popular in espresso blends and instant coffee.
Brew Methods
Your brew method might have the biggest impact on caffeine levels. It all comes down to contact time and your coffee-to-water ratio. Methods with longer contact time, like French press or cold brew, give water more time to pull caffeine out of the grounds. Cold brew in particular often ends up with a high caffeine concentration because it uses a long steep time (often 12–24 hours) and usually a higher coffee-to-water ratio.
Meanwhile, espresso is a quick and concentrated dose that results in more caffeine per ounce (roughly 50 - 90mg of caffeine per shot). However, a standard cup of drip coffee will likely be about 80 - 100+ mg of coffee). By volume, a concentrated shot of espresso would win. But if you compared it to cup size...the drip would win.
So whether you’re reaching for a light roast, a dark roast, or dialing in your next cold brew, you’re getting caffeine. And if all else fails, just remember: the best coffee is the one that gets you going.
