How to Identify Coffee Roast Levels by Color and Sound

If you’ve ever stared at a bag of coffee beans wondering whether it’s light, medium, or dark roast, you’re not alone. Roast level determines much of your cup’s flavor—brightness, body, sweetness, and bitterness—but without clear standards, 'light' in one country might mean 'medium' in another. How do you really know what you’re buying or roasting?

The Specialty Coffee Association of America (SCAA) created an eight-level roast color standard using Agtron readings, while traditional methods rely on timing the bean’s first and second cracks during roasting. Together, these tools help roasters and drinkers identify roast level consistently.

What Is a Coffee Roast Level?

Roasting transforms green coffee beans through heat, typically reaching 450°F (232°C), and lasting around 12–16 minutes. During this process, moisture drops by 15–25%, beans expand in size, turn brown, and develop aromatic oils. The roast unlocks acidity, sweetness, bitterness, and aroma—but over-roasting can mute origin flavors. Each level from light to dark brings different taste characteristics.

The SCAA’s Eight-Part Roast Color Guide

The SCAA developed its standard using an infrared caramelization detection tool called Agtron. This technology measures bean surface color and sorts roasts into eight distinct shades, ranging from very light to very dark. These eight color blocks serve as a visual reference for roasters worldwide, allowing more consistent communication of roast degree. While the system is precise, many coffee professionals still use traditional names alongside it.

Traditional Roast Levels Named by Region

Before standardized systems, roast levels were often named after countries or cities, reflecting local taste preferences—for example, 'French roast' or 'Italian roast.' These names became synonymous with darker roasts, though definitions varied. The practice grouped roasts from lightest to darkest but lacked precision, causing inconsistency among roasters. Still, these terms persist informally in coffee culture.

How Roasters in Taiwan Judge Roast Level by Sound

In Taiwan, many roasters determine roast degree by listening for the bean’s cracking sounds during roasting. Here’s how it typically breaks down:

• Light Roast : Coffee is dropped just at or slightly after the start of the first crack. This roast highlights bright acidity and is often used in commercial or canned coffee.
• Medium / City Roast : Coffee is released between the end of the first crack and before the start of the second crack. This level, also called 'breakfast roast,' balances origin character with moderate development—common for beans like Colombia or Brazil.
• Full City Roast : Coffee is dropped at the beginning of the second crack. At this stage, acidity, sweetness, and bitterness are said to achieve balance, and oils begin to surface. It’s a favorite for single-origin profiles.
• Italian / French Roast : Roasting continues well past the second crack. Beans become dark brown to nearly black, oils rise to the surface, and the roast flavor dominates. This level is often used for espresso.

What Happens During the Roast Process?

Roasting is a complex chemical journey. Starting as hard, green seeds full of chlorogenic acid, beans lose much of their initial acidity as heat breaks it down into more pleasant fruit acids such as citric, malic, and acetic acids—if roasted correctly. Under-roasting leaves beans grassy and astringent; over-roasting burns off origin flavors, leaving a smoky, bitter taste.

Here’s a rough timeline of physical and sensory changes:

• At 5–7 minutes, moisture escapes and beans turn from pale green to yellowish-orange, releasing aromas reminiscent of roasted vegetables.
• First crack (around 8–10 minutes) signals the start of light roast territory. Beans expand, turning cinnamon or light brown, and acidity is prominent.
• By 10–11 minutes, beans reach a medium or ‘city’ roast—brown, balanced, and often enjoyed with milk. This is also called a breakfast roast.
• At 12–16 minutes, second crack begins. Oils emerge, beans darken to deep brown, and flavors grow richer. This is the full city stage, where some find ideal balance.
• Beyond second crack lies dark roast territory, including French and Italian roasts. Beans become shiny with oil, very dark brown or black, and develop bold bitter-sweet notes suited for espresso.

Flavor Development by Roast Level

Different roast levels emphasize different flavor aspects of the bean:

• Light Roast: Bright, acidic, and tea-like. Great for tasting origin traits but often considered too mild for coffee enthusiasts.
• Medium Roast: Balanced acidity, body, and sweetness. Popular for single-origin coffees like Yirgacheffe or Brazilian beans.
• Full City: Often considered the sweet spot where acidity, sweetness, and bitterness converge. Oils begin to show on the bean surface.
• Dark Roast (Italian/French): Bold, bitter, and often smoky. Low acidity, higher bitterness, and prominent roast flavors. Common in espresso blends.

Note: Acidity and bitterness vary by coffee origin even within the same roast category.

Frequently Asked Questions

What is the SCAA roast color standard?

The SCAA uses an Agtron device to measure the color of roasted coffee beans, sorting them into eight distinct roast levels from light to dark. This provides a numerical and visual reference to standardize roast color across the industry.

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

Agtron is an infrared caramelization detection tool that measures the color of roasted coffee beans. It assigns a numerical value to bean surface color, helping roasters classify roast levels consistently on a scale from very light to very dark.

When is first crack and what does it mean?

First crack usually occurs around 8–10 minutes into roasting, when beans expand and make a popping sound similar to popcorn. It signals the beginning of light roast levels and a major chemical shift inside the bean.

When is second crack and why does it matter?

Second crack starts around 12–16 minutes into roasting. It produces a sharper, more rapid sound than first crack and indicates deeper roast development. Roasters often drop beans at the start or during second crack for darker styles like Full City, French, or Italian roasts.

Does roast level affect caffeine content?

Yes. Lighter roasts retain slightly more caffeine than darker roasts, as some caffeine is lost during extended roasting. However, the difference per bean is minimal, and roast level has a greater impact on flavor than caffeine levels.

Recommended FrontStreet Beans for Roast Level Study

Explore FrontStreet Coffee’s Yirgacheffe for bright, high-acid light to medium roast profiles, showcasing fruity and floral notes ideal for tasting subtle roast differences. Their Brazil Queen Manor offers a balanced medium roast with nutty sweetness, perfect for practicing city to full city range. For dark roast lovers, the PWN Golden Mandheling reveals bold, syrupy body with low acidity—great for exploring French or Italian styles. Freshly roasted within 5 days · Orders placed before 17:00 ship the same day · Next-day delivery across most of Guangdong Province.