Dark Roast VS Medium Roast Coffee Beans

Perhaps you’ve heard people say that dark roast coffee beans give you that true coffee taste. Yet, others will tell you that medium roasts highlight the essential flavors of good coffee.

Do roast levels really make a difference? Yes, they do.

When you buy the right roast for the tastes you love and the brewing methods you own, you get more satisfaction out of your coffee.

Let’s get to the truth about dark roast vs medium roast. By the end of this article, you’ll know how they’re roasted, how they taste, and which roast is best for you.

How coffee roasting changes the beans

Coffee doesn’t start out life as that delicious-smelling brown bean you get out of a bag at your favorite café.

In fact, once the coffee is harvested, processed, and dried, coffee beans look and smell quite plain. Unroasted coffee beans have a silvery-green color and are (not surprisingly) referred to as green coffee.

Green coffee tastes…well, green. It has a grassy or pea-like taste that is not at all appealing.

When I visit coffee farms, I’ll usually pick a bright red coffee cherry off a plant and pop it into my mouth. While the cherry itself tastes mild with a bit of tartness, the seed (or bean) isn’t pleasant and doesn’t yet taste good.

What gives coffee beans their beautiful brown color, alluring smells, and satisfying tastes is the roast process.

Let’s dive into how coffee roasting changes flavors and other characteristics.

Roasting Coffee Is A Process

There are many kinds of coffee roasters. 

If you’ve got a small batch, you can roast your coffee beans at home on tiny kitchen countertop roasters. In contrast, large coffee brands roast coffee beans in immense 75 kg roasters. 

Overall, the most common coffee roasters are drum roasters or hot air.

What they all have in common is that they apply a certain amount of heat to the bean for a certain amount of time. That junction of time and temperature is called the roast profile.

During the coffee roasting process, roasters heat coffee beans to between 370 and 540 degrees Fahrenheit. The whole roasting process is fast, taking anywhere from 10 minutes and 16 minutes.

When a roaster receives green coffee beans, they decide which roast level is best for that particular coffee. The roast level can vary from a light roast to a dark roast. When those coffee beans are roasted, many factors are changed, including the flavors.

When I first started roasting, I did an exercise that helped me understand how roasting changes the bean. I took just one type of green coffee and roasted it several different ways.

What did I change? Just the temperature and the roasting time. And the results astounded me.

I found that simple changes made each roast seem completely different. It was like I was drinking totally different coffees. Yet, it was the same bean, roasted in different ways.

When coffee beans are roasted, they go through significant physical and chemical changes. The aromas and flavors in the beans begin to develop. Heat modifies acidity and changes the sugars present in the coffee bean.

There are between 800 and 1000 aroma compounds in coffee beans. Roasting coffee beans not only affects those compounds, but it creates new ones!

That’s why roasted coffee is so fascinating and complex and why roasting is a vital art in creating those fantastic coffees we love.

How long the coffee beans are roasted and at what temperature changes everything. The flavors, sweetness, body, bitterness, and acidity will be different depending on the roast.

Light Roast Coffee Beans

As heat builds up inside the coffee bean, it gradually changes from green to yellow to brown. This browning stage during roasting is an exciting one. It’s when the Maillard Reaction kicks in.

Don’t be alarmed by the fancy name. The Maillard Reaction simply refers to a stage that happens to anything that gets cooked. It’s when heat begins to transform the sugars and amino acids.

If you’re finding that hard to understand, think of grilling a piece of meat or chocolate chip cookies in the oven. The enticing smells are actually the result of the Maillard Reaction, the heat acting on the food.

I say it’s an exciting roasting stage because this is when the aromas and flavors in the coffee bean begin to develop. You know you hit the Maillard Reaction stage in roasting when things start to smell delicious. You perceive the sweetness and aromas of the roasting coffee.

At about 10 minutes into roasting, heat builds up inside the coffee bean to the point that the bean structure begins to break down. It literally cracks under all that pressure. Not surprisingly, that roasting stage is called first crack.

When the coffee beans hit first crack they’re considered to be roasted enough to be consumed. At this point, the roast will be quite light.

Acidity will be high, and you can fully appreciate the origin of the coffee. Since the sugars in the coffee haven’t fully caramelized, light roast coffees tend to have reduced sweetness.

Medium Roast Coffee 

As you continue roasting the coffee past the first crack, sugars continue to caramelize. The oils inside the coffee beans start to migrate out of the bean and coat the surface, although the beans still won’t look oily at this point.

You’ve entered the range of medium roast. The coffee still hasn’t reached second crack.

In the United States, medium coffee beans are generally one of the most commercial coffees. They are at times called American, Breakfast, or Fully City.

Dark Roast Coffee

As the heat continues to work on the beans in the roasting process, you’ll get to the point of second crack. During second crack, the rest of those oils that were inside the coffee beans liberally coat the surface of the beans.

The beans get quite dark in color as they pass second crack. The bean takes on the flavor of the roast rather than the flavor of the coffee itself or its origin.

You’ve hit dark roast. Dark roast is often called by names such as French Roast, European, or Italian Roast. The difference has to do with the coffee company, not the coffee roast.

Dark Roast VS Medium Roast Comparison

So, what’s the difference between a dark roast and a medium roast coffee?

Dark roast coffee beans

When you open a bag of dark roast beans, you’ll notice the beans have a beautiful shine on the surface. Oily in appearance, dark roast beans can seem more luxuriant. Depending on how long past second crack they were roasted, they have a rich, dark color.

Many coffee drinkers love the fact that dark roast beans will often taste like dark chocolate or toast. They will be more bitter, especially in the aftertaste, and they may have a smoky flavor.

The oils that came out of the coffee beans during second crack give the brew an intensified feeling of body. Acidity will completely disappear at this point.

Medium roast coffee beans

A medium roast is, of course, lighter in color. The roasted beans will have a bit of oily shine on the surface from the first crack, but it should be minimal. Medium roast beans will generally have less body than darker roasts.

You can often distinguish the characteristics of the region in which the coffee was grown, known as the terroir. For instance, any natural notes of orange blossoms, grapes, or nuts come through.

Medium roast beans still retain some acidity, but it’s lower than a light roast. It generally has more balanced flavor and aromas and more pronounced sweetness. A medium roast coffee will still have some of the notes of origin.

How can you best brew medium and dark roast coffee?

You may want to choose your coffee beans based on the brewing method you have.

If you are searching for a pour-over method that compliments your dark roast, French Press does well. The French Press will accentuate the body, giving you a strong drink that packs a punch.

A dark roast is more soluble, which means it extracts faster. When using a dark roast, you may want to shorten your brew time, so you don’t get over-extracted and bitter coffee.

However, dark roast beans tend not to shine in other pour-over methods. The roasting process will have roasted over the intricate flavors that pour-overs are so good at highlighting.

If you have an espresso machine at home, you may find it easier to pull an excellent shot of espresso with a dark roast. Espresso machines accentuate acidity, so the lower acidity in a dark roast can be a good match.  If you use a lighter coffee bean to brew espresso, you may under-extract the coffee and get a sour cup.

When it comes to picking a brewing method to use with a medium roast, you can get more creative. A lighter coffee will have more intricate flavors and extract slower.

A medium roast does well in espresso, though you may have to adjust the extraction time.

You can develop the inherent sweetness of a medium roast in a V60.

But, If you like a brighter cup of coffee, brew in an Aeropress.

If you want to develop complex yet delicate flavors like herbal or floral notes, reach for your Chemex.

Is medium or dark roast coffee stronger? 

Coffee drinkers ask me if a dark roast is a stronger coffee. First, we should define what you might mean when you say stronger coffee. There are two ways to define “strong.” Is the taste stronger, or does the coffee have more caffeine?

Do dark roast coffee beans have a stronger taste? Not surprisingly, dark roasts do have a more roasted taste. They can also taste more bitter.

Some coffee drinkers feel that those roasted, bitter tastes create a stronger coffee, with a more “coffee” taste.

Medium roasts are generally not as strong. They have less of a roasted taste and should be less bitter.

On the other hand, medium roast levels allow the flavors of origin can come through, which might actually seem stronger to you.

For instance, you might get an intense blueberry taste from your medium roast. That can be quite strong. For some people, the strong taste of blueberries in their coffee is pleasant, while it’s a bit shocking for others.

Regarding caffeine content, which has higher caffeine levels: a medium or dark roast? Many people feel that dark coffee has more intense caffeine content.

However, the difference in caffeine content between a medium roast and a dark roast is normally slight. If the beans were roasted at unusually high temperatures, they would actually lose caffeine. So at times, a dark roast can have less caffeine than a medium roast.

On the other hand, coffee beans that were roasted dark have lost moisture along the way. Those beans weigh less. So per weight, dark coffee beans may have a higher amount of caffeine per weight. The difference in caffeine, however, is slight.

Summary

In the dark roast vs medium roast challenge, which one wins? As with anything edible or drinkable, the answer is the same: The kind you like.

As a coffee drinker, you should purchase the coffee beans that make you feel satisfied.

If you want your coffee beans to highlight the flavors of the origin, opt for a medium roast. On the other hand, a dark roast has a fuller body and slightly bitter taste.

Karen Attman

Karen Attman

The Coffee Lady

Karen Attman is a published author and specialty coffee expert. Otherwise known as the coffee lady, Karen is the Latin American Coffee Academy founder and has previously written about coffee for CNN, Sprudge, and Eater.