Coffee Roast Level Explained: The Best Coffee Beans for You

Taste is subjective, and a cup of coffee that one person loves might not suit another. To find your ideal brew, you must learn what the roast type means and how different heat levels transform the bean.

From light roasts that offer high acidity to medium and dark roasts that become heavier and fuller-bodied, the primary roast levels dictate what the final cup of coffee tastes like.

What are Coffee Roast Levels?

Coffee roast levels essentially refer to the heat-driven transformation of green beans into the aromatic brown beans we recognise. What’s more, the type of roast directly dictates the beans’ final colour, flavour profile, and inherent acidity.

The difference between light, medium and dark roast is characterised by these defining factors:

• Flavour Profile: Lighter roasts highlight the unique characteristics of where the bean was grown. Darker coffee roasts emphasise the caramelisation and smoky bitterness of the roasting process itself.
• Agtron Scale: This is a professional colour-based system ranging from 25 to 95. In coffee roast charts, higher numbers (90+) indicate very light beans, while lower numbers (under 50) represent very dark roasts.
• Temperature: This is a major factor, with light roasts typically kept 200°C below, while darker types of coffee roasts can reach 240°C or higher.

It’s also worth noting that the beans are categorised from the shortest to the longest roast times. But what exactly are the four types of coffee roasts?

1. Light Roast: Bright Acidity and Maximum Origin Flavour

The light roast level serves as the purest expression of the coffee bean’s origin flavours. Because the beans are roasted for a shorter time, they do not reach high enough temperatures to release internal oils, resulting in several distinct characteristics:

• Colour and Oil: These beans are light brown in colour with a noticeably dry surface, as no oil has migrated to the exterior.
• Flavour Profile: You can expect a toasted-grain taste, accompanied by pronounced high acidity.
• Caffeine and Body: Surprisingly, a light roast retains most of the caffeine content compared to its darker counterparts. It also features a thin, light body that feels tea-like on the palate.
• Common Examples: Popular variations include the Cinnamon Roast and the New England Roast.

2. Medium Roast: Balanced Flavour and Versatile Body

For many coffee enthusiasts, the medium roast represents the sweet spot, offering a middle ground between origin characteristics and the roasting process. This roast level is also popular because it achieves a complexity that appeals to a wide variety of palates:

• Colour and Oil: These beans feature a rich, medium brown colour. Much like lighter coffee roasts, the surface remains dry and free of visible oil.
• Flavour and Acidity: You will find that it lacks the grainy taste of a light roast. Instead, it exhibits a more balanced flavour, aroma, and acidity, often possessing hints of chocolate or nuts.
• Body and Caffeine: It possesses a more substantial body than a light roast, providing a fuller mouthfeel. While the caffeine content is somewhat lower with longer roasting times, it still contains more caffeine than darker varieties.
• Common Examples: The American Roast and City Roast are the most frequent types found in this category.

3. Medium-Dark Roast: Heavy Body and Bittersweet Profile

As the coffee beans spend more time in the drum, they undergo further chemical changes, creating a more intense sensory experience. This roast level marks the point where the heat begins to transform the cellular structure of the bean, resulting in several notable shifts:

• Colour and Oil: These beans have a richer, darker colour, and you will notice a light sheen of oil on the surface as the internal fats begin to migrate outward.
• Flavour Profile: The taste shifts toward a bittersweet profile with much less acidity. At this stage, the roast flavour begins to dominate the original bean characteristics, leaning into spicy or deep cocoa notes.
• Body and Mouthfeel: One of the main differences between medium-dark and other roast levels is the heavy body, which offers a much thicker, more substantial mouthfeel than lighter or medium roasts.
• Common Examples: You will often see this profile labelled as a Full City Roast or a Vienna Roast.

4. Dark Roast: Low Acidity, Smoky, and Roast-Centric

The intense heat used to create a dark roast results in a bold, robust profile that many associate with traditional espresso. The beans lose their original brightness in favour of these deep, charred coffee characteristics:

• Colour and Oil: These beans are dark brown to nearly black, featuring a pronounced oily sheen on the surface. With a dark roast, you’ll often see a visible layer of oil in your cup once brewed.
• Flavour and Acidity: Expect a bold, bitter, and smoky or even “burnt” taste. The acidity is also low, as the roasting process eclipses the bean’s original floral or fruity notes.
• Caffeine Content: Because the beans are subjected to heat for the longest time, the total caffeine content is substantially lower than in lighter roasts.
• Common Examples: Classic varieties include the French Roast and the Italian Roast.

How Roasting Changes the Coffee Bean

Roasting is a complex chemical process where heat develops the sugars and oils locked within the green coffee seed. Consequently, the roast levels determine these physical transformations on the bean:

• Acidity: As the coffee roast level increases, organic acids break down, decreasing acidity as the roast darkens.
• Body (Mouthfeel): The texture or “weight” of the coffee generally increases with darker roasts. This is due to the development and migration of internal oils that provide a coating sensation on the tongue.
• Flavour Profile: There is a constant trade-off between origin and process. For example, lighter coffee roasts highlight origin notes like floral or fruit flavours, while darker roasts highlight bittersweet and smoky notes created by the roaster.
• Surface Oil: As the bean structure breaks down under high heat, internal oils are forced to the surface. This is why darker beans appear shiny, while lighter roasts remain matte and dry.

Regional Coffee Origins: General Flavour Tendencies

While the specific coffee roast level plays a massive role in your cup, the journey begins with the bean’s origin. However, generalising the flavour is difficult because factors such as altitude, ripeness, and processing methods create an infinite number of variations.

Yet, these major growing regions do offer distinct tendencies that help you navigate a coffee cart menu:

• Central America (e.g., Guatemala, Nicaragua): Beans from this region are typically very balanced, offering a refined mix of sweetness and bright, fruity acidity that yields a clean finish.
• South America (e.g., Colombia, Brazil): Colombian coffee tends to be sweeter and less acidic with distinct nutty hints, whereas Brazilian beans often feature chocolatey notes and a creamier mouthfeel.
• Africa (e.g., Ethiopia, Kenya): Often considered among the purest kinds of coffee, African origins are fragrant and possess an extremely diverse flavour profile. You can expect it to be complex, fruity, and floral with a full body regardless of the roast.
• Asia (e.g., Indonesia, Vietnam): This region is the “wild card” of the coffee world, as its beans tend to be earthier and darker in profile. Generally, the types of coffee coming from this place are less acidic but offer a much more complex, heavy-bodied experience.

Find Your Perfect Match

From the acidity of a light roast to the smoky, bold profile of a dark roast, choosing the right coffee roast level depends entirely on your flavour preference. If you enjoy discovering the unique “terroir” of a bean, lighter roasts are your best bet. However, if you prefer a rich, bittersweet finish with a heavy body, a darker roast will satisfy your palate.

At Nineteen95, we utilise our knowledge of these roasting profiles to select speciality-grade Colombian beans that are perfectly developed for our coffee menus.

Book our mobile coffee cart services today or join our next coffee-making workshop in Singapore to taste the difference for yourself.