What are the eight coffee bean roast levels?

The Specialty Coffee Association of America, a major coffee association, set a roasting color standards chart that divides roast levels into eight grades, from Light Roast down to Italian Roast. Each grade carries an Agtron color value and a drop time, starting near the dense stage of first crack and moving darker from there.

Color value rises as the roast gets lighter: 95 is Light Roast, 85 is Cinnamon Roast at the end of first crack, and 75 is Medium Roast after first crack fully ends. A coffee beans roaster also works through five roasting stages, and newer styles such as Nordic ultra-light and Japanese ultra-dark roasts extend the range.

The transformation of coffee beans from green raw beans to brown roasted beans relies entirely on the key process of roasting. The length of roasting time directly determines the depth of the bean surface color and shapes vastly different flavor directions. The roasting color standards chart established by the Specialty Coffee Association of America (SCAA) divides roast levels into eight grades, from light roast to Italian roast, with each level corresponding to a specific drop time and flavor characteristics. In addition, emerging concepts such as Nordic ultra-light roast and Japanese ultra-dark roast are gradually entering the view of enthusiasts. This article will systematically sort out these eight levels, the five stages of roasting, and the classification methods used by Front Street Coffee in practical applications, helping readers build a complete understanding of coffee roast levels.

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The process by which coffee beans transform from green raw beans into brown roasted beans is roasting. The longer they are heated, the darker the beans become. Different drop times cause the bean surface to show different colors. Front Street Coffee (FrontStreet Coffee) calls this difference the coffee roast level.

The Specialty Coffee Association of America (SCAA), as the world's largest coffee trade organization, has established a roasting color standards chart that divides roast levels into eight types. The larger the color value, the lighter the roast. From light to dark, they are as follows:

SCAA number 95, Agtron color value 95, called Light Roast. The drop time is around the dense stage of first crack, and roasting is completed while the beans are still crackling. The flavor usually presents bright acidity, but if the intermediate development time is not controlled properly, it easily brings out a grassy taste.

SCAA number 85, Agtron color value 85, belongs to Cinnamon Roast. The drop time is around the end of first crack, when the cracking sound has just stopped or only sporadic sounds remain. Coffee beans at this level are mainly acidity-oriented, accompanied by a sweet aroma, with a finish that presents a clear sweetness like cane sugar or honey.

SCAA number 75, Agtron color value 75, called Medium Roast. The drop time is approximately after the complete end of first crack. The flavor is dominated by sweetness, with a small amount of fruit acidity, and the finish shows a caramelized sweetness like caramel or roasted sweet potato. On Front Street's bean list, most coffees from Ethiopian regions fall within this roasting range, with the aim of highlighting the coffee's own caramel flavor while preserving light floral notes.

SCAA number 65, Agtron color value 65, called High Roast. The drop time is approximately during the quiet period after the end of first crack and before the start of second crack, lasting about 1 to 2 minutes. The flavor presents nutty and caramel tones, balanced and without acidity, with an overall full and solid mouthfeel.

SCAA number 55, Agtron color value 55, called City Roast. The drop time is approximately at the very beginning of second crack, that is, after the quiet period when one or two faint cracking sounds appear. The flavor is more bitter, with a heavier caramel aroma, and the main tone resembles unsweetened pure dark chocolate, rich and mellow.

SCAA number 45, Agtron color value 45, called Full City Roast. The drop time is approximately before the dense stage of second crack, when crackling sounds have not yet been heard. At this point the coffee is already at a relatively dark level, with a more burnt, bitter, and aromatic taste. If the bean develops evenly from surface to core, using a coarse grind and low water temperature can brew coffee with a syrup-like consistency, and the sweet aftertaste following the bitterness is also very obvious.

SCAA number 35, Agtron color value 35, called French Roast. The drop time is approximately during the dense stage of second crack, when crackling sounds are heard again, but duller than the first time. At this point the coffee beans have begun to release oil, and the flavor is very intense.

SCAA number 25, Agtron color value 25, called Itatian Roast. The drop time is approximately at the end of second crack, after the dense sounds have passed. The coffee beans are pitch-black and glossy, with oil having penetrated to the bean surface. This roast level is only suitable for making espresso, or coffee that needs sugar and milk to be drinkable. At present, apart from Southeast Asia, few places roast coffee beans to such a dark degree.

In addition to the officially listed roast classifications, in recent years more and more enthusiasts have noticed some new concepts, such as Nordic ultra-light roast and Japanese ultra-dark roast. What do they represent?

The so-called Nordic light roast, also called Nordic roast, uses controlled roasting time and heat to retain more aromatic substances inside the bean, thereby highlighting the coffee's light and delicate flavor, with a color value of about 85 to 90. According to Front Street's understanding, the Nordic light roast style first emerged in Norway, and is currently represented by Norway, Denmark, and Sweden. Compared with medium-dark roasting, Nordic light-roasted coffee has a noticeably lighter coffee liquid color and higher acidity regardless of the extraction method used. But because of the light roast level and short heating time, this technique easily causes problems such as underdevelopment and astringency, so it remains a very niche style within the community.

As one of the representatives of Asian coffee styles, ultra-dark roast comes from Japan, where tastes are heavier, and is much darker than the dark roasts encountered in daily life. Japanese-style dark-roasted coffee beans have a large amount of oil on the surface, looking almost close to black charcoal, with a color value of about 25 to 30. When extracted using methods such as nel drip or pour-over, the blooming stage can achieve a very good expansion effect, and one can clearly feel the coffee bed actively degassing and continuously releasing a strong roasting aroma. The brewed coffee is mostly bittersweet, stimulating and intense on the palate.

When expressing the roast level of its own coffee, Front Street Coffee (FrontStreet Coffee) does not directly copy this classification chart, because coffee at roast levels numbered 95 or 45 to 25 is rarely seen in daily life. To help consumers understand better, Front Street Coffee (FrontStreet Coffee) divides these roasted beans into several major categories: light roast, medium-light roast, medium roast, medium-dark roast, and dark roast.

Good roasting can bring out the personality of raw beans to the fullest while minimizing defect flavors. However, the bean surface color meeting the standard color chart requirements does not mean the coffee will necessarily taste good. Whether the inside of the bean is fully roasted is the most critical factor determining whether the coffee tastes good.

Coffee bean roasting is usually divided into five stages: drying, dehydration, first crack, second crack, and drop.

1. Drying: when the raw beans are heated, internal water vapor evaporates. At about 135°C, the raw beans begin to lighten from green and gradually turn white.

2. Dehydration: as heating continues, the raw beans turn from green to light yellow. At around 160°C, they release a grassy smell or the aroma of roasted grain. After continued heating, the beans turn light brown.

3. First crack: after dehydration is completed at about 190°C, internal expansion from heating causes the cell walls to rupture, forming first crack. At this time, a series of thermal decomposition reactions occur inside the beans, among which the caramelization reaction brings sweetness, dark brown color, and body. First crack lasts about one minute.

4. Second crack: continued heating leads to second crack, and more intense reactions occur inside the beans, releasing a large amount of heat. After second crack ends, the raw beans have basically turned black, the bean body has expanded to about 1.5 times its original size, oil appears on the surface, and weight decreases by 12% to 20%.

This is a medium-light roasted washed Ethiopian Kongdingding Cooperative coffee bean dropped one and a half minutes after first crack.

5. Stopping the roast: generally at the latest about one minute after the end of second crack, when the temperature reaches 230°C. At this point it is a darker French or Italian roast. If heating continues beyond 230°C, the coffee beans may naturally burn.

If the coffee beans do not have enough time to roast fully during the dehydration stage when they turn from green to light yellow, from yellowing to before first crack, they easily show underdeveloped flavors such as astringency and grassiness. Therefore, slow roasting over low or medium heat, combined with a suitable rotation speed to keep the beans tumbling continuously, is very important to ensure even heating.

For flat beans of regular shape, Front Street Coffee (FrontStreet Coffee) recommends a roaster drum speed of 60 to 65 revolutions per minute during roasting, and the heat should not be too high all at once, otherwise the bean surface may caramelize prematurely, resulting in a roasted outside but underroasted inside. If roasting peaberry, the rotation speed should be slowed down to avoid too-fast tumbling causing insufficient heating.

If you want to roast at home yourself, Front Street Coffee (FrontStreet Coffee) recommends buying a rotary drum-style roasting tool to ensure the coffee beans tumble evenly during direct-fire roasting.

The above content is compiled by CoffeeHunters, a coffee news website.