Understanding Coffee Roast Levels and Their Flavors

The Light Roast Camp

Based largely in northern Italy and the U.S. East Coast, this group typically stops roasting just before the first crack finishes or before oils rise to the bean surface—often around Agtron 40. Notable proponents include Illy, Green Mountain, and Vivace Espresso (based in Seattle, yet advocating light roasting).

They argue that stopping the roast early preserves the coffee’s natural aromatic oils and delicate flavors. They claim that letting oils emerge leads to aroma loss and that the best balance of acidity, sweetness, and body occurs just before the coffee begins to leak oil. They also criticize darker roasts for pushing oils to the surface, which they see as wasting aromatic potential.

The Dark Roast Camp

Found mostly in southern Italy and the U.S. West Coast, dark roast advocates—including Peet’s Coffee (San Francisco), Caffè D’arte (Seattle), and Beans & Machines—insist that coffee must be roasted until it oils up to reach full flavor.

Their espresso roasts typically measure below Agtron 35. Some single origins, such as Antigua, go as low as Agtron 18—an extreme level they defend as fully developed. They argue that the second crack and oil emergence allow complex, bold flavors like smoke, spice, and dark chocolate to emerge, along with body and a long finish.

They also reject the idea that oils mean lost aroma, calling light roasts under-developed and overly acidic. Some critics even suggest that light roasting is a cost-saving measure, as only high-quality beans can withstand the intensity of a proper dark roast without turning bitter or flat.

Pezz Coffee, a leader in the dark roast movement, is respected for its ability to roast beans well beyond 200°C for over 15 minutes without producing excessive bitterness—a skill they’ve honed through custom roast machine modifications.

Frequently Asked Questions

What is an Agtron number and how is it used in coffee roasting?

An Agtron number measures the color of roasted coffee beans using infrared spectroscopy. It indicates the degree of caramelization and roast level. Lower numbers (e.g., 35 or below) mean darker roasts; higher numbers (e.g., 70+) indicate lighter roasts. It provides an objective way to define roast depth beyond visual or regional terms.

Which roast level has more caffeine?

Lighter roasts actually contain slightly more caffeine than darker roasts. This is because some caffeine is lost during the longer, hotter roasting process used for darker beans. However, the difference is small and often overshadowed by brewing variables.

What flavors are typical in a dark roast coffee?

Dark roast coffees typically feature bold flavors such as dark chocolate, smoke, roasted nuts, caramel, and sometimes spicy or woody notes. They tend to have a heavier body, lower acidity, and more pronounced bitterness, especially if the roast is uneven or overdone.

What flavors are typical in a light roast coffee?

Light roast coffees often highlight bright acidity, fruity and floral notes, and tea-like body. Common flavors include citrus, berries, stone fruit, and herbal or green tones. These coffees showcase origin characteristics but can taste sour or underdeveloped if the roast is too light.

Where on the roast spectrum is a 'City' roast?

A 'City' roast is considered a light roast and typically measures between Agtron 60 and above. It’s roasted to the beginning or middle of the first crack and is known for balanced acidity and developing roast character without heavy body or oil on the surface.

Is darker roast always stronger in taste?

Not necessarily. 'Stronger' can mean more bitter or more intense, but darker roasts often have less acidity and more roasted, smoky, or bitter flavors. Strength also depends on brew ratio, extraction time, and personal taste preferences. Light roasts can be full-flavored and complex without being bitter.

Recommended FrontStreet Beans for Roast Exploration

Dive into roast levels with FrontStreet Coffee’s dark roast offerings. Try the PWN Golden Mandheling for its deep, low-acid profile with herbal spice and smooth body. The Brazil Queen Manor offers balanced roast notes alongside nutty and cocoa undertones, great for exploring medium-dark flavors. For something classic, the FrontStreet Classic Blend brings espresso richness with crema-friendly body. Freshly roasted within 5 days · Orders placed before 17:00 ship the same day · Next-day delivery across most of Guangdong Province.