Once upon a time, when the world was first introduced to coffee, we would always assume a darker roast was better. After all, drinking dark, bold coffee was the sign of a hardened, seasoned palette. Plus, there’s more caffeine. Right? It didn’t help much that good quality beans were a scarcity, so most roasters would roast it black as charcoal to hide uneven tasting or outright bad beans.
Now, the world has changed. With the introduction of third wave specialty coffee, a wider variety of roast levels are available, and the global trend has started shifting towards lighter roasts. For example, Starbucks. A mega coffee conglomerate, once dead set in their signature dark roast, now has a “blonde” roast on menus worldwide.
What’s the difference between a light roast, a medium roast and a dark roast? How do I pick one that suits my taste preference best? Does a darker roast really have more caffeine? I’ll be guiding you through the main differences, how they taste, and tips for you to pick your favourite roast level. Now, let’s take a quick look at how coffee is roasted!
The Roasting Process
All coffee starts its life as a green bean. It has no aroma and no taste. They’re edible, yes, you could grab a handful and chew on it. Mind you, it wouldn’t taste very good – you’d be better off chewing cardboard. All green beans must be roasted before they can be used to brew coffee.
The most common specialty coffee method of roasting beans is via a drum roaster. Green beans are poured into a drum that spins. A heat source from the bottom heats and roasts the beans in it. During roasting, the beautiful aroma and magnificent flavours start coming out.
As the beans get hotter and hotter, water in each bean escapes. This causes the outer skin or the shell of the bean to dry up and turn dark. Eventually, the bean gets so dry, it reaches a point where it “cracks”. Depending on how long and how hot the roast is, a bean can crack once or twice. Hence, you’ve got the terms “first crack” and “second crack”.
Imagine it as toast. Fresh bread is soft and squishy. The more you toast bread, the browner and darker it gets. It becomes stiff and if you fold it, it makes a lovely crackling sound. For coffee beans, the cracks are one of the main indicators of a light vs medium vs dark roast.
Roast Levels Guide
#1 – Light Roast
When green beans are roasted to a temperature of 350°F – 400°F (180°C – 200°C), they are usually just before the stage of the first crack. The surface is relatively matte/smooth in texture, and isn’t oily to touch at all. Light roast beans take on a pale brown colour.
Taste-wise, light roasts are the best at preserving the origin flavour of the beans. You’ll get light, citrusy, floral and fruity flavours. Light roasts are amazing for soft brew methods, such as pourover or an AeroPress. You can taste really clean, crisp flavours unique to how and where the coffee was grown.
The downside is that light roasts have the highest acidity, which means that the margin for error is a lot less forgiving. If under-extracted, which happens easily, you’ll be drinking some sour coffee.
Light roasts are also called Half City, Light City, New England, Cinnamon or Blonde roast.
- COLOUR: Light brown
- SURFACE: Smooth and matte
- TASTE: Floral, fruity, vibrant, acidic
#2 – Medium Roast
At a temperature of 400°F – 430°F (200°C – 220°C), the beans have cracked for the first time, with a nice, solid brown colour. You’ll be able to see a slight sheen or shine on the surface of the beans.
Medium roasts bring out a bit more of the darker, more bitter notes to balance out the acidity in the beans. As a result, you get a smooth tasting, well-rounded coffee. Less sharp and less sour. Some examples of flavour notes you can find in a medium roast are toffee, raisin, chocolate and caramel. Great for most soft brew methods and espresso.
Medium roasts are by far the most commonly consumed in the United States, with a 51% lead (according to a 2020 study by Statista.com).
The downside is that the delicate flavours might not shine through that easily as opposed to a dedicated light roast or dark roast.
Also known as a City roast, Breakfast roast, regular roast or American roast (gee, I wonder why).
- COLOUR: Brown
- SURFACE: Smooth and slightly shiny
- TASTE: Balanced, well-rounded
#3 – Medium-Dark Roast
The beans have cracked for the second time! The temperature is now climbing to 430°F – 450°F (220°C – 230°C), and the high heat has started to push the oils out from inside the beans to the surface of the beans. A rich, dark brown colour is coated by a small amount of oil on the surface.
A darker, heavier taste starts to rise from the beans. Taste-wise, it is bittersweet, chocolatey, nutty and earthy. Any acidity is mostly gone, and the flavour profile here is more bitter than sour. Medium-dark roast beans produce lovely crema, thanks to the oils on the surface, so it works amazing for espresso. Because the taste is darker and more robust, it can also withstand the addition of milk for a latte or cappuccino, and still retain its flavours without being drowned out.
The downside is that it’s super easy to screw up, over-extract your coffee and drink burnt, woody coffee that tastes like coal.
Another name for a dark roast is a Full City roast.
- COLOUR: Dark brown
- SURFACE: Slightly oily, shiny
- TASTE: Strong, earthy, chocolatey, nutty
#4 – Extra Dark Roast
Above 460°F (240°C), the beans are basically burnt. Oops. The beans have long gone past the second crack, are being charred close to black, and are drenched in oil on the surface.
I call it the burnt roast, because really – that’s what it is. You’ll taste more charcoal and soot than anything else. It’s bitter and harsh. This roast type is super common on supermarket shelves. It’ll clog your grinder, your taste buds, and your soul. My advice? STAY AWAY.
They come by a bazillion names, probably to make them sound more attractive, but here, we know it is a futile attempt. High, Continental, New Orleans, European, Espresso roast, Viennese, Italian, French, etc..
- COLOUR: Close to black
- SURFACE: Extremely oily and shiny
- TASTE: Burnt, bitter, ashy
An Important Footnote: Medium-Dark vs Dark Roast
Extra dark, “burnt”, Italian/French roasted beans are pretty much never found amongst specialty coffee roasters and shops. It basically doesn’t exist to them. Hence, many will simply name their beans as light, medium or dark to keep things simple (such as in that picture above which I took in a micro roastery).
Their “dark roast” will be the equivalent of our medium-dark roast explained in this article. Good roasters take huge care in bringing out a bean’s flavour, so their dark roast profile will still taste good.
The only time you should be wary of a dark roast is if it comes off a supermarket shelf. Especially if you don’t know where, how or who has roasted it. These non-specialty coffee beans will usually be the extra-dark, near-burnt roast type. This is the one you should avoid.
The Relationship Recap
Below are a couple of useful pointers to remind yourself of how the roast level affects the taste. Generally, they go as follows:
- The lighter the roast, the higher the acidity (the more sour it will taste).
On the converse, the darker the roast, the more bitter it is.
- The lighter the roast, the brighter the taste notes (e.g. floral and citrus).
For a darker roast, the taste notes will be deeper and darker.
- Lighter roasts are more recommended for pourover coffee (e.g. AeroPress, Hario V60 or a Moccamaster).
Darker roasts are more recommended for espresso.
Tips on Choosing the Roast Level
The best way for you to pick the roast profile is based on what you like to taste best. Coffee is all about savouring and enjoying every bit of the drink, from the initial aroma right through till the aftertaste. Don’t get something you know you’ll hate. Here’s a little simplified guide below:
- Go for a LIGHT ROAST if you enjoy light, bright and vibrant coffee. You’ll be able to pick out floral and fruity notes that really showcase a coffee’s true colours.
- Go for a MEDIUM ROAST if you want a well-balanced flavour with less acidity, that works for a variety of brew types. A medium roast is extremely well-suited for beginners looking to develop their palette, as it is not as sharp or bitter.
- Go for a MEDIUM-DARK ROAST if you prefer a more traditional and darker coffee. Chocolate, nutty and earthy notes will come through stronger.
Remember, use this as a loose guide – this isn’t 100% accurate all the time. A skilled roaster can definitely bring out chocolatey notes from a light roast, or highlight a particular fruit in a dark roast. Look at the packaging of your beans, and keep an eye out for the taste notes of the “body” – this is the main bulk of the flavour.
Personally, my favourite is a medium roast. As much as I love fruits, I’m not a fan of high acidity in coffee, and I prefer the roast bring out slightly deeper notes to tie in and balance off my coffee. So it’s really down to your personal taste preference!
What About the Caffeine Content?
There’s a whole array of confusing myths out there about the relationship between a coffee’s roast level and the caffeine quantity in it. Some say a darker roast is stronger and hence has more caffeine. Then some would argue the longer a bean is roasted, the more caffeine is lost, so lighter roasts are higher in caffeine. Which one do you believe?
Let’s clear this up once and for all: bean for bean, caffeine content stays pretty much the same, regardless of roast level.
“The truth is that caffeine is extremely stable during the roasting process.”
Kicking Horse Coffee performed a study on this matter. If you compare one light roast bean to one dark roast bean, they would have about the same level of caffeine.
The confusion comes in whether you scoop or weigh your coffee. Remember how I said that the longer a bean is roasted, the more water escapes and the more it dries up? It becomes less dense. So for a fixed weight (e.g. 10 grams), there will always be more dark-roasted beans to make up for the lighter beans.
Hence, if you weigh your beans before your brew, dark roasts will have more caffeine.
But, if you measure your beans by a rough scoop, lighter roasts will have more caffeine.
Again, this is only a very small difference, so don’t stress out too much about how much caffeine you’re getting in a light roast versus a dark roast – most of the time, if you drink the same amount, it is negligible.
Roast Levels: Roasted!
I hope you now have a clear idea of the differences between a light, medium, medium-dark and dark roast coffee. It comes down to how long the beans are roasted for, and what flavours are revealed by the heat.
There is no right or wrong when it comes to your preference of which roast you prefer. You may get some coffee snobs shaking their head when you tell them you prefer the chocolatey notes of a darker roast. They’ll tell you to always get a light roast. But just 10 years ago these coffee snobs would have been the ones singing praises about dark roast coffee!
Know what you like, and don’t feel like to have to prove anything to others about your preferred coffee. After all, life’s too short for bad coffee, so get out there and make every cup count!