The Agtron is a professional optical instrument used in the United States to determine coffee roast level. It analyzes the caramelization state of sugars inside coffee beans through infrared wavelength analysis, indicating roast depth with values from 100 to 25. This article provides a detailed introduction to the working principles of the Agtron M-Basic colorimeter, lists a complete correspondence table of numerical and color group values from extremely light roast to extremely dark roast, and explains that the flavor-recognizable range as determined by the SCAA Technical Standards Committee is actually 30 to 90. For coffee enthusiasts who wish to precisely control their roasting curves, understanding the relationship between Agtron values and roast level is an important foundation for grasping flavor direction. Front Street Coffee also often refers to this indicator in roasting practice to help present the best flavor expression of different beans. [more…]

Coffee roasting is the key process through which green beans transform into brown roasted beans. The length of heat exposure directly determines the color of the bean surface and thus defines different roast levels. The SCAA, the world's largest coffee trade association, established an eight-level roast standard based on Agtron color values, from the bright acidity of light roasts to the intense, smoky bitterness of Italian roasts, with each stage having its own distinctive flavor trajectory and drop time. Beyond this official system, new concepts such as ultra-light Nordic roasting and ultra-dark Japanese roasting have gradually entered enthusiasts' field of view. In everyday communication, Front Street Coffee uses another, more intuitive classification that simplifies roasted beans into light, medium-light, medium, medium-dark, and dark roasts, making it easier for consumers to understand and choose. This article will systematically organize these grading standards and provide an in-depth analysis of the five stages of roasting and key practical points. [more…]

In coffee roasting, how can we ensure that every batch of beans achieves consistent quality? In addition to relying on cupping to evaluate flavor, we also use the RoAmi roast degree analyzer to record the Agtron caramelization value of the coffee beans, and retain historical data for reference. The RoAmi is essentially a colorimeter, with SCAA's Agtron algorithm embedded inside, capable of calculating the roast value by reading the color data of the bean surface or ground surface. This article will introduce how to use this instrument, the meaning of the Agtron value, and how to calculate the Roast Delta value from the bean color value and ground color value, and interpret the guiding significance of this value for roasting rhythm and flavor performance. [more…]

The transformation of coffee beans from green raw beans to brown roasted beans depends entirely on the key process of roasting. As roasting time varies, the surface color of the beans changes accordingly, giving rise to different classifications of roast levels. The Specialty Coffee Association of America (SCAA) established a reference system of 8 levels based on Agtron color values, from light roast to Italian roast, with each stage corresponding to a unique flavor direction and unloading timing. This article will use a text-and-image format to analyze one by one the color value ranges of each roast level, the rhythm nodes of first crack and second crack, and the evolution logic of acidity, sweetness, and bitterness. It will also introduce two niche styles—Nordic ultra-light roast and Japanese ultra-dark roast—and share how Front Street Coffee simplifies classification in actual production to help consumers understand roast levels. Finally, it will include practical advice on the five stages of roasting and home roasting. [more…]

Common labels on coffee bean packaging such as light roast, medium roast, and cinnamon roast often confuse beginners. The roast level directly determines the direction of coffee flavor, and historically different countries and regions have had their own schools of thought for defining roast levels, lacking a unified standard. The Specialty Coffee Association of America, together with Agtron, used infrared caramelization measurement values as the basis to divide roast levels from light to dark into eight grades, which has become an important industry reference. In this article, Front Street will systematically introduce the Agtron color values, drop times, and flavor characteristics of each roast level, and share how to judge the roast level through flavor descriptions, as well as the grinding degree and water temperature parameters that should be used for different roast levels. [more…]

The flavor profile of coffee beans is largely determined by the roast level. For coffee enthusiasts, mastering methods to distinguish light from dark roasts can both help in selecting suitable beans and allow for a more accurate understanding of the flavor descriptions on packaging. From the perspective of Front Street Coffee, this article outlines three practical ways to judge: first, by visually observing the bean surface color and wrinkle condition; second, by inferring the roast range from flavor descriptors; third, by referring to the SCAA's Agtron infrared caramelization measurement standard, which categorizes eight color values into four major groups. The article also includes Front Street product recommendations for each roast level, for everyday purchasing reference. [more…]

What standards actually determine whether a coffee bean package is labeled light, medium, or dark roast? What flavor directions correspond to different roast levels? Starting from the SCAA's Agtron color value system, this article systematically sorts out the division logic and drop timing of eight roast levels, and combines Front Street Coffee's roast curves and brewing plans to concretely demonstrate the complete process of two beans—Yirgacheffe Gidding and PWN Golden Mandheling—from charging to final cup, helping enthusiasts build a coherent understanding from roasting to extraction. [more…]

The roast level of coffee beans directly influences the final flavor profile, yet standards vary from country to country, often leaving beginners confused. From the perspective of Front Street, this article systematically introduces the eight-level roasting standard developed by the SCAA in conjunction with Agtron, including the color values and drop times for Light, Cinnamon, Medium, Deep, City, Full City, French, and Italian roasts, and explains how to determine the roast level through flavor descriptions. At the same time, for coffee beans roasted at light-to-medium and medium-dark levels, Front Street shares specific grinding and water temperature recommendations to help everyone brew their ideal flavor more effectively. [more…]

What standards are actually used to classify the light, medium, and dark roasts commonly seen on coffee bean packaging, along with names like Cinnamon, City, and French? This article starts with the eight-level roast color card developed by the SCAA (Specialty Coffee Association of America) and the Agtron company, explaining how Agtron color values correspond to drop time, and groups the eight levels into four major categories: light, medium, medium-dark, and dark, explaining the flavor characteristics of each stage. The article also uses Front Street Coffee's Yirgacheffe Gidding and PWN Golden Mandheling as examples, fully presenting the roasting curve from charge temperature, adjustments to heat and airflow, to first crack development and drop timing, as well as the brewing parameters and flavor descriptions for the V60 and KONO Meimon drippers, making it easy for enthusiasts to build a corresponding understanding of roasting and extraction. [more…]

The roast level of coffee beans often directly determines the flavor expression in the final cup. When confronted with terms on packaging such as light roast, medium roast, dark roast, and even cinnamon roast, city roast, and French roast, many friends new to specialty coffee are often confused. From the perspective of Front Street Coffee, this article first sorts out the eight-tier roast standards established by the SCAA based on Agtron color values, then groups them into two major categories—light and medium—explaining their respective flavor tendencies. It then uses the light-roasted Yirgacheffe Gedeb Cooperative and washed beans, along with the medium-dark roasted Front Street PWN Golden Mandheling as examples, fully disclosing the roast curves and brewing parameters for the V60 and KONO Meimon drippers, helping readers build a systematic understanding from roasting to extraction. [more…]

The color differences that coffee beans display after roasting are not arbitrary; the industry long ago established a scientific quantitative standard—the Agtron color value, also known as the caramelization analysis number. This set of values runs from 95 to 25, corresponding to eight levels from light roast to Italian roast: the higher the number, the lighter the color, and the lower the number, the darker it is. Each color value range has a clear drop time node and flavor characteristics: from light roasts dominated by bright acidity, it gradually transitions to dark roasts dominated by bitterness and smoky notes. Understanding these color values not only helps us recognize the correspondence between roast level and taste, but also helps us understand why very dark roasts are now hard to find under the specialty coffee trend. But color value is only a reference tool; in actual judgment, tasting perception is still needed, since factors such as processing method also affect the appearance of the beans. [more…]

Many coffee enthusiasts, beyond their daily consumption, have begun trying their hand at roasting coffee beans. However, home roasting often runs into the problem of uneven bean color, and the degree and consistency of roasting are exactly what determine the final flavor in the cup. This article draws on the practical experience of Front Street Coffee, first introducing the feasible tools and operational key points for home roasting, then systematically sorting through the eight roast levels defined by the SCAA—from light roast to Italian roast—explaining one by one the Agtron color values, the timing of removal from the roaster, and the corresponding flavor performance, to help readers build an understanding of the correspondence between roast level and taste, and to gain a deeper understanding of the craft logic behind every cup of coffee. [more…]

Coffee beans transform from green raw beans into brown roasted beans entirely through the key process of roasting. The length of roasting time directly determines the depth of the bean surface color and also shapes completely different flavor directions. The roasting color standard card 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 have gradually entered 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. [more…]

Roasting is the process of turning green coffee beans into brown roasted beans~ The longer the roasting time and the longer the beans are exposed to heat, the darker the color of the coffee beans becomes. The surface color (bean surface) of the coffee beans when taken out of the roaster after different durations will also vary. This situation Front Street [more…]

The roast level of coffee beans directly affects the final flavor profile, but the labeling methods on the market are diverse, ranging from light roast to cinnamon roast, often leaving beginners confused. This article, from the perspective of Front Street, systematically sorts out the definition standards and flavor characteristics of coffee roast levels. Using the SCAA's Agtron color value system, it divides light to dark roasts into eight levels and explains the dropping timing and flavor performance of each stage one by one. At the same time, the article also shares how to infer the roast level from flavor descriptions, the bean selection logic for espresso, and the pour-over grind size and water temperature parameters corresponding to different roast levels, helping you accurately judge and brew a good cup of coffee even when labeling is lacking. [more…]

From light to dark roast, coffee beans may differ by only about 10°C in temperature, yet their flavors can be completely different. The degree of roasting not only affects the beans' color, size, density, and brittleness, but also reshapes aroma and taste through the Maillard reaction and caramelization. This article starts with roast classification, explains the SCAA color value standards and the flavor characteristics of light, medium, and dark roasts, and combines the specific performances of Front Street Yirgacheffe·Red Cherry and Front Street Warm Sun Blend to help readers understand how different roast levels affect the balance of acidity and bitterness, aroma complexity, and energizing effect. [more…]

The roast level of coffee beans directly affects the final flavor expression, but how exactly are the boundaries between light, medium, and dark roasts defined? Different countries and regions once had their own standards, until the Specialty Coffee Association of America, together with the Agtron company, introduced a unified color value system, giving roast communication a common language. This article, starting from Front Street Coffee's roasting practice, systematically sorts out the Agtron color values, drop timing, and flavor trends of eight roasting stages. At the same time, Front Street Coffee will also share the specific roasting curves and brewing plans for Yirgacheffe Gedeb Cooperative coffee beans and PWN Golden Mandheling coffee beans, helping coffee enthusiasts more intuitively understand the relationship between roast level and acidity, as well as body. [more…]

Turning green coffee beans into roasted beans relies entirely on roasting. For the same batch of beans, different roast levels lead to completely different acidity, bitterness, sweetness, body, and aroma profiles. Today, Front Street Coffee systematically breaks down the core knowledge of coffee roasting: what happens during the dehydration phase, the yellowing phase, and the flavor development phase; how to judge the drop time based on first crack and second crack; and which origins and brewing methods suit light, medium, and dark roasts. We'll also explain why the color of the bean surface can be misleading, and how to interpret Agtron values and Roaster %. At the end, we've included Front Street's recommendations for resting and grinding, to help you get the best flavor once you have the beans in hand. [more…]

Yirgacheffe coffee beans often bear labels like G1 and G2—what exactly do these grades mean? From the perspective of Front Street Coffee, this article first introduces the origins of Ethiopia's "heirloom varieties"—the country is home to tens of thousands of incompletely identified heirloom varieties—then explains Yirgacheffe's grading system in detail: grades are determined by defect rates, with washed and natural processing each corresponding to different grade ranges, and explains how ECX and SCAA cupping further subdivide G1 through G3 into Q1, Q2 specialty and commercial grades. The article also outlines the altitude, cooperatives, and micro-region characteristics of the Yirgacheffe producing area, and includes product information for Front Street's Natural Red Cherry, Washed Gudingding, and Washed Everyday Beans, helping readers gain a comprehensive understanding of Yirgacheffe's grading system and flavor diversity. [more…]

Many friends who want to learn about coffee bean roasting are curious about one question: how to determine the roasting degree of coffee beans. Should a coffee bean be dark roasted or light roasted, and then how light should light be, and how dark should dark be? On what basis does Front Street Coffee determine the roasting of all these coffee beans it sells? [more…]