Before green coffee beans reach our hands, they often go through many stages, during which defects are almost unavoidable. Some defects are obvious at the green bean stage, yet once roasted they may be cleverly concealed. The SCAA (Specialty Coffee Association of America) has established strict grading standards for specialty Arabica coffee, covering multiple dimensions such as defect types, moisture content, aroma, and bean size. This article will systematically sort out the SCAA's defect classification rules and scoring requirements, explain in detail the causes of various defective beans and their impact on cupping flavor, and help enthusiasts develop a keen eye for identifying specialty coffee. At the same time, the article retains relevant recommendations from the Front Street brand for readers' reference. [more…]

Defective beans are generally considered in the specialty coffee world to affect the flavor performance of a cup of coffee. If you have the habit of buying coffee beans and brewing at home, do you need to specifically pick out defective beans before brewing? In fact, green coffee beans undergo grading after processing, and most grading systems include a defect rate indicator. The number of defects in high-grade coffee beans has already been pressed to a very low level. From green bean grading, removal before roasting, to screening after roasting, with layer upon layer of checks, there is basically no need to worry about defective bean issues when buying roasted single-origin coffee beans. However, some coffee beans that look like defects are actually normal phenomena. Front Street Coffee has summarized several common types of situations that are easily misjudged, to help everyone distinguish them accurately. [more…]

The content of defective beans directly affects coffee quality and grade classification. Taking Brazil as an example, the local system uses a "deduction method," grading based on the number of defective beans per 300 grams of main beans. In addition, coffee usually requires hand sorting during processing, and only by fully mastering the types and characteristics of defective beans can they be effectively removed. So exactly how many types of defective beans are there? This article will use illustrated explanations to introduce ten common defective beans one by one, including shell beans, stones, moldy beans, fermented beans, dead beans, immature beans, shell beans, insect-damaged beans, black beans, and cocoa beans, explaining their causes, appearance characteristics, and negative effects on coffee flavor, laying the foundation for subsequent learning about defective bean selection. [more…]

Many coffee enthusiasts, when first encountering coffee beans, often misjudge defective beans based on unusual appearance. In reality, true defective beans are mainly concentrated at the green bean stage, and most have already been screened out at the producing region and roasting stages. Among the beans consumers buy day to day, those covered in wrinkles, with cracks, or on the lighter side in color are often not defects, but normal phenomena brought about by light roasting, high-altitude cultivation, or specific processing methods. This article systematically sorts out the classification standards for green coffee bean defects, distinguishes true defective beans from appearance traits that are easily misunderstood, and introduces Front Street Coffee's practice of double screening before and after roasting, helping readers build a more accurate basis for judging quality. [more…]

Many coffee enthusiasts have come across bloggers sharing their experiences with bean sorting before brewing. The main purpose of sorting beans is to remove defective beans that carry negative flavors. This article focuses on this topic, systematically outlining the types, causes, and identifying characteristics of common coffee defects, including moldy beans, insect-damaged beans, black beans, and the more unusual quaker beans, while explaining their specific impact on coffee flavor. It also addresses a practical question: if the chosen merchant is reliable enough and the beans have undergone multiple rounds of sorting before and after roasting, is it still necessary to sort beans by hand yourself? Drawing on Front Street Coffee's sorting process and a 15g Panama Boquete Geisha as an example, the article offers a useful reference answer. [more…]

The SCAA Coffee Flavor Wheel is a core tool for specialty coffee enthusiasts to identify flavors, yet many people are still unfamiliar with it. This article systematically breaks down the left-right structure of the flavor wheel: the right side, the normal flavor spectrum, reveals the three major aroma sources of fermentation, sugar browning, and dry distillation, while the left side, the negative flavor spectrum, corresponds to the defective flavors produced by improper green bean processing, storage, and roasting. It also explains in detail the deduction rules for different defects in SCAA cupping—serious defects deduct 4 points, minor defects deduct 2 points—and how roasting and organic matter loss, although not deducting defect points, can lower flavor performance. The article includes the latest high-definition Chinese-English flavor wheel images and retains Front Street Coffee's communication channels, making it suitable for readers who want to gain a deeper understanding of coffee sensory evaluation. [more…]

As an agricultural product, coffee beans vary significantly in quality, so a grading system is needed to standardize quality and provide reference for buyers. However, the geographical environments and cultivation models of global producing regions differ enormously, making it impossible to measure them with a unified standard; each region can only adapt to local conditions. Currently, mainstream grading methods fall into three major categories: screen size, altitude/hardness, and defect rate, and many countries combine them or even add cupping to compensate for shortcomings. This article will systematically sort out the logic and representative producing countries of these three grading methods, with a focus on analyzing how Kenya grades solely by bean size, and introduce the grading practices of Colombia, Ethiopia, Jamaica, Indonesia, Brazil, and other countries. Front Street Coffee will also share related brand product information to help coffee enthusiasts understand the meaning behind green bean grades. [more…]

Many pour-over coffee enthusiasts often have doubts about the appearance of the beans after purchasing single-origin beans, and even mistake normal beans for defective ones. There are two main reasons for this misunderstanding: first, consumers who only come into contact with roasted beans rarely see truly defective beans; second, they treat coffee beans as products of an industrial assembly line, assuming they have a fixed standard appearance. In reality, most defective beans are already controlled at the green bean stage, and after roasting there is also manual sorting. This article will systematically sort out the definition of defective beans, the defect rate requirements in green bean grading, and focus on explaining several commonly misjudged situations such as peaberry, burst beans, uneven color, and shriveled wrinkled beans, to help readers view the appearance of coffee beans more rationally. [more…]

For more specialty coffee knowledge, please follow our WeChat official account: Front Street Coffee (FrontStreet Coffee). Many friends, while drinking coffee at Front Street, ask our baristas, "What is Yirgacheffe G1 and Yirgacheffe G2?" "What is Kenya AA, AB?" What is Guate... [more…]

Yirgacheffe is one of Ethiopia's most representative specialty coffee regions, but what exactly is the difference between the commonly found Front Street Yirgacheffe G1 and G2 coffee beans? Which grade is higher? Behind this lies Ethiopia's complex coffee grading system. Starting from CoffeeHunters' review, this article systematically sorts out Ethiopia's coffee grading standards, compares the differences between G1 and G2 in defect rate, cupping score, and flavor performance, and helps coffee lovers gain a deeper understanding of the secrets of Yirgacheffe's grades. [more…]

Coffee enthusiasts often ask in the shop exactly what the difference is between Ethiopia's G1 and G2, what Kenya AA actually means, and what Costa Rica's SHB grade signifies. These combinations of letters and numbers actually reflect how each producing country evaluates the quality of green coffee beans. Due to differences in history, trade, climate, and terrain, different origins have developed their own grading systems, with evaluation criteria covering multiple dimensions such as defect percentage, bean size, growing altitude, green bean density, and processing method. This article will systematically sort out the origins of coffee grading and introduce, one by one, the green bean grade standards of representative producing countries such as Ethiopia, Kenya, Colombia, Jamaica, Costa Rica, Panama, Guatemala, El Salvador, Honduras, and Brazil. [more…]

As the birthplace of coffee, Ethiopia's grading system directly affects the quality and flavor expression of coffee beans. The Yirgacheffe region is world-renowned, but what exactly is the difference between the commonly seen Front Street Yirgacheffe G1 and G2 coffee beans on the market? Behind this lies the evolution of Ethiopia's coffee grading system. From CLU to ECX, from simple defect counting to a comprehensive score combining physical characteristics and cupping flavor, the grading standards have undergone major changes. This article will systematically review the historical development and specific standards of Ethiopian coffee grading, compare the grading differences between washed and natural processing, and through three dimensions—green bean appearance, roasted bean appearance, and cupping flavor—deeply analyze the actual differences between Front Street Yirgacheffe G1 and G2, helping coffee enthusiasts understand the quality implications behind the grade numbers. [more…]

Blue Mountain coffee is all the more precious because of its scarce production, but the reason it has long maintained a reputation for high quality is inseparable from a rigorous grading system. Even if the coffee beans do indeed come from Jamaica's legally designated Blue Mountain region, they must still be carefully classified according to the size specifications and defect ratio of the green beans before their grade can be finally determined. This article will comprehensively sort out the grading logic of Blue Mountain coffee from No. 1 to Peaberry, analyze key indicators such as defect rate and bean screen size, and explain why, beyond grade, the vintage and the specific estate are also important factors determining the flavor expression of Blue Mountain. At the same time, by combining the roasting and brewing characteristics of Front Street Coffee's Blue Mountain coffee, it presents its signature nutty notes and balanced mouthfeel, helping coffee lovers understand this legendary coffee more systematically. [more…]

Ethiopian coffee has always won the favor of many coffee lovers with its affordable prices and rich floral and fruity aromas. But faced with the bewildering array of grade labels on the market, such as Yirgacheffe's G1 and G2, many people are not clear on exactly how they differ and which is more worth buying. This article will start with the price level of Ethiopian coffee, combine it with specific beans from Front Street Coffee, and then delve into the evolution of the country's coffee grading system—from the early CLU defect-count grading to the ECX scoring system that combines physical characteristics with cupping flavor—breaking down one by one the logic of grade classification under washed and natural processing, and focusing on comparing the substantive differences between G1 and G2 in defect rate and cupping score, to help you make more rational purchases of Ethiopian coffee. [more…]

Colombia's coffee grading system is more complex than that of most Central American producing countries. It is based not only on altitude, but also on a set of export standards built around defect rates and screen size. The Excelso grade adopted by the FNC is the highest export grade for Colombian green coffee. The burlap sacks are marked with "Excelso-Café de Colombia" and accompanied by a quality certificate. This article covers everything from the grading logic, screen size requirements, and defect deduction rules to the three most common export grades, and uses a washed Caturra from the Huila region as an example to explain green coffee traceability and cupping flavor performance, helping coffee enthusiasts understand the meaning behind Colombian green coffee labels. [more…]

When two café owners ask each other about the grade of beans they use, what lies behind the question is a complex set of international coffee grading logic. Brazil's defect-score system, Central America's altitude standards, East Africa's screen sizes—each producing country has developed a completely different quality evaluation system based on its own national conditions. This article will systematically sort out three mainstream grading methods: by origin altitude, by green bean screen size, and by a composite evaluation method combining screen size and defective bean ratio, and will explain in detail Brazil's unique three-tier grading system and its strict cupper culture. Whether you are a newly initiated enthusiast or a seasoned professional, understanding these standards can help you judge coffee quality more accurately and also provide a reference for everyday purchasing. [more…]

Yirgacheffe is a highly representative coffee-producing region in Ethiopia, and its G1 and G2 grades often confuse enthusiasts. Starting with Ethiopia's coffee grading system, this article sorts out the rating evolution of CLU and ECX, explains in detail the scoring standards of washed and natural processing in terms of physical characteristics and cupping quality, and compares the actual differences between Front Street Coffee Yirgacheffe G1 and G2 in green bean appearance, roasted bean appearance, and flavor. Through cupping, it was found that although the two share citrus, fruit tea, honey, and berry tones, G1 is superior in cleanliness and aroma refinement, while G2 is slightly thinner. It is suitable for coffee enthusiasts who want to gain an in-depth understanding of Yirgacheffe grades and purchasing. [more…]

Yirgacheffe, as a representative coffee-producing region in Ethiopia, frequently has its G1 and G2 grades mentioned, but what exactly is the difference between the two? This article begins with the evolution of Ethiopia's coffee grading system, first introducing the old system based on defect rates, then explaining the new regulations after the ECX introduced cupping scores in 2009, and explaining why naturally processed beans can also obtain G1 and G2 grades. Subsequently, using washed Yirgacheffe as an example, it compares the actual differences between Front Street Coffee's Gutingding (G1) and Front Street Coffee's washed Yirgacheffe everyday beans (G2) in terms of green bean appearance, defect proportion, and brewed flavor, helping readers understand the quality implications behind the grades. [more…]

Yirgacheffe is one of Ethiopia's most representative specialty coffee regions, and Front Street Yirgacheffe G1 and Front Street Yirgacheffe G2 are the two beans most easily available for everyday purchase. What exactly is the difference between G1 and G2? Which one is of better quality? To answer these questions, one must first understand Ethiopia's coffee grading system. From the evaluation perspective of Front Street Coffee, this article sorts out the origins and development of the two grading systems, CLU and ECX, analyzes the respective scoring dimensions of washed and natural processing, and presents the real differences between Front Street Yirgacheffe G1 and G2 through a direct comparison of green bean appearance, roasted bean appearance, and cupping flavor. [more…]

Yirgacheffe, as Ethiopia's most representative coffee region, has long been favored by coffee enthusiasts for the floral and fruity flavors produced by its washed and natural processing methods. But do you know how the G1 and G2 grades are actually divided? And what substantial differences exist between them? This article will systematically sort out Ethiopia's coffee bean grading system, tracing the evolution from CLU to ECX, explaining in detail the scoring standards for washed and natural processing methods in terms of physical characteristics and cup quality, and through an actual cupping comparison of Front Street Coffee's Yirgacheffe G1 and G2, reveal the specific differences between the two in terms of cleanliness, aroma complexity, and defect rate, helping you make a clearer judgment when purchasing. [more…]