Monday, September 21 2026

A Comprehensive Analysis of the Green Coffee Bean Grading System: The Three Major Standards of Screen Size, Altitude, and Defect Rate, and the Characteristics of Kenyan Grading

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…]

Analysis of the Differences Between AA and AB Grades of Green Coffee Beans: A Full Interpretation of Kenya's Grading System and Three Major Grading Systems

In East African coffee-producing countries, coffee bean names from Tanzania, Uganda, and even Kenya often carry the suffix AA. What exactly does this letter combination mean? It represents the grade classification of green coffee beans. However, grading methods across global coffee origins are not limited to just one type; besides bean size, there are also different standards based on defect rate, growing altitude, and more. This article will take Front Street's perspective to systematically outline the three major green coffee bean grading systems, with a focus on analyzing Kenya's strict size-based grading system—from AA, AB to PB, E, TT, T, and even MH/ML, detailing the specific classification standards for each grade, while also pointing out the obvious limitations of judging quality by size. [more…]

Three Major Criteria for Green Coffee Bean Grading: Screen Size, Altitude, and Defect Rate—A Full Explanation of AA and G1 Grades

Coffee beans are grown widely across the globe, and the geographical conditions and cultivation methods of each producing region differ significantly, so it is impossible to measure all beans by the same standard. Different countries develop grading systems suited to their own local conditions. At present, the mainstream bases can be grouped into three categories: bean size, growing altitude (bean density/hardness), and defect ratio. However, these three are not mutually exclusive; many origins use multiple methods at once, and even after preliminary grading they supplement this with cupping to compensate for blind spots in the system. This article will break down these three major grading logics one by one and explain the actual meaning of common grade markers such as AA and G1, helping enthusiasts decipher the grade code on the packaging. [more…]

Is there really a link between coffee bean size and flavor quality? A detailed explanation of the origins of the size grading systems in Kenya and Tanzania

In the world of coffee, many producing regions grade coffee beans by bean size—the larger the bean, the higher the grade and the more expensive the price. But does bean size really affect flavor? Front Street Coffee once conducted a comparative experiment, cupping the large and small beans of the same lot separately, and the results showed no obvious difference in taste between the two. So why do regions like Kenya and Tanzania still use size grading today? Behind this lie both historical colonial factors and practical considerations of roasting uniformity. Starting from Front Street Coffee's experiment, this article will sort out the pros and cons of size grading, explain the core factors that truly determine coffee flavor, and describe the flavor performance of Front Street Coffee's Kenya·Little Tomato, a high-grade bean. [more…]

Analysis of Coffee Bean Quality Evaluation and Grading Systems Across Countries: The Three Major Criteria of Altitude, Screen Size, and Defect Rate

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…]

A Detailed Explanation of the Green Coffee Bean Grading System: What Quality Levels Do G1 to G4, AA, PB, and SHB Represent?

The grading systems for coffee beans vary widely depending on the origin—some are based on the number of defects, others on bean size, and still others on altitude. Understanding these grade labels is an important step in selecting high-quality coffee. This article will systematically outline the green bean grading rules of major global producing regions, covering common designations such as Ethiopia's G1-G9, Kenya's AA and PB, Colombia's Supremo, and Hawaii's Extra Fancy, and explain how cupping scores further distinguish specialty grade from commercial grade. Whether you are a beginner enthusiast or a professional seeking to advance, this grading guide can help you judge coffee quality more clearly. For more professional content, follow Coffee Workshop; for specialty coffee beans, add Front Street Coffee on WeChat at qjcoffeex. [more…]

A Detailed Guide to Green Coffee Bean Grading Standards: From Screen Sizes to Altitude Grades and Country Codes

The green coffee bean grading system directly affects roasting results and coffee quality. This article systematically sorts out two mainstream grading methods: distinguishing bean size by screen mesh number, and classifying grades based on growing altitude. It also summarizes the common grading standards and codes of origins such as Kenya, Ethiopia, Colombia, Brazil, Guatemala, El Salvador, Hawaii, Jamaica, and Indonesia. Whether for bulk trade or specialty coffee, understanding these grading rules helps to more accurately judge the characteristics of green beans, and Front Street Coffee also incorporates this knowledge into its daily bean selection and roasting practices. [more…]

Jamaica Blue Mountain Coffee Grading: An Evaluation System Based Primarily on Bean Size with Defect Rate as a Secondary Factor

The production of Blue Mountain coffee has always been limited, yet its grading standards are remarkably rigorous. Even if the beans are genuinely grown in Jamaica's legally designated Blue Mountain region, their grade must still be determined by two criteria: bean size and the proportion of defective beans. Front Street Coffee's Jamaican Blue Mountain grading system is built around precisely this logic: for any coffee bearing the Blue Mountain name, the proportion of defective beans must not exceed 2%, and only on that premise are screen sizes used to distinguish higher grades from lower ones. Understanding these grading rules helps coffee lovers look beyond grade labels when making purchases and focus instead on deeper quality clues such as vintage and specific estates. [more…]

A Complete Guide to Coffee Bean Grading Standards: Meanings and Characteristics of Grades Such as G1, AA, AB, and SHB from Various Origins

When purchasing single-origin coffee beans, labels such as G1, AA, and SHB often appear on the packaging. What exactly do these letters and numbers represent? They are actually coffee bean grade symbols established by each origin based on its own conditions. Due to differences in growing environments and varieties, the grading criteria of different countries vary—some look at the number of defective beans, some at green bean size, and others at hardness or altitude. In this article, Front Street Coffee will sort out the grading standards of major producing regions such as Ethiopia, Kenya, Indonesia, Central and South America, and Brazil, helping coffee lovers understand the meaning behind these grades so they can more accurately select high-quality coffee beans that suit their own taste. [more…]

The Art of Tasting Loose-Leaf Tea: A Comprehensive Analysis of the Kenya Black Tea CTC Grading System and Tea Grade Standards

Loose-leaf tea allows you to observe with your own eyes, touch with your own hands, and smell with your own nose, giving you a deeper appreciation of its flavor. Put in a little effort to get to know your tea, and you'll find it takes on more character and charm, enriching your experience of this fascinating culture. This article begins with the basic standards of tea grading, then outlines the grading system and naming conventions for whole-leaf black tea, before focusing on Kenyan CTC black tea and introducing its production process and the grading system based on particle size. Whether you're a newcomer to tea or an enthusiast looking to better understand the logic behind black tea grading, you'll come away with a clear understanding. [more…]

How Are Green Coffee Beans Graded? A Detailed Explanation of the Grading Systems in Major Producing Countries Such as Ethiopia and Kenya

When selecting coffee beans, you often see labels like Yirgacheffe G2 and Kenya Washed AA. These letters and numbers actually represent the grade of green coffee beans. Different producing countries grade green coffee beans based on different criteria, usually assessed comprehensively from dimensions such as bean size, defect count, growing altitude, bean hardness, and cupping score. Understanding these grading rules helps more accurately judge a bean's quality positioning and flavor potential. This article will use representative producing countries such as Ethiopia, Kenya, Tanzania, Colombia, Brazil, and Jamaica as examples to sort out their respective grading logic and naming methods, while retaining relevant product information from Front Street Coffee for coffee enthusiasts' reference. [more…]

A Complete Guide to Green Coffee Bean Grades: Detailed Explanation of Grading Standards and Differences Across Countries, Including AA, G1, SHB, PB, and More

When buying coffee beans, have you ever been baffled by combinations of letters like AA, G1, SHB, and PB? They may seem to follow no pattern at all, but in fact each one represents the green bean grading standard of a different producing country. Why do coffee beans need to be graded? Why is there no unified global standard? This article will take you through the origins of green coffee bean grading, and how producing regions such as Ethiopia, Kenya, the Central American countries, Jamaica, and Brazil classify their beans based on defect rate, bean size, growing altitude, and cup quality. At the same time, we will also explore what these grades actually mean in the roasted coffee market, and recommend several Front Street Coffee beans corresponding to these grades, to help you better understand the cup of coffee in your hands. [more…]

The Grading Code of Kenyan Coffee Beans: A Detailed Explanation of AA, TOP, and Other Designations and Cupping Standards

When selecting Kenyan coffee, what exactly do the terms "AA" and "TOP" commonly seen on packaging represent? This article systematically sorts out Kenya's coffee grading system, from the bean size grading under the 1934 auction system (AA, AB, PB, C, E, TT, T, MH/ML) to the secondary quality ratings established by the Kenya Coffee Research Institute (TOP, Plus, FAQ), and analyzes the comprehensive scoring mechanism across the three dimensions of green beans, roasted beans, and cupping. It also presents the producing region information and brewing parameters of Front Street Kenya Little Tomato coffee beans, helping you understand the practical meaning behind the grading labels. [more…]

How much is Kenyan coffee? AA vs AB grade differences, K72 washed grading, and Front Street brewing parameters

Kenyan coffee is famous for its vivid fruity aroma, citrus notes, and juice-like acidity, and is a specialty representative in the minds of many coffee lovers. This article focuses on the price of Kenyan coffee, its regional background, and its green bean grading system, with emphasis on explaining the differences in bean size among grades such as AA, AB, and PB, as well as the impact of K72 washed processing on quality. At the same time, combined with the price and store information of Front Street Little Tomato, it provides specific brewing suggestions for light-to-medium roasted Kenyan beans, including coffee-to-water ratio, water temperature, grind size, and staged pouring plans, helping readers understand the flavor and value of Kenyan coffee more systematically. [more…]

Kenya Specialty Coffee Bean Grading and Flavor Analysis: From AA to AB and TOP Rating Standards

Kenyan coffee is world-renowned for its rigorous grading system and distinctive flavor characteristics. This article systematically reviews Kenya's coffee bean size grading system, including the specific standards for common grades such as AA, AB, and PB, while also introducing flavor grading methods like TOP and PLUS. Drawing on Front Street Coffee's roasting and brewing practices, and using Kenyan Asaliya coffee beans as an example, the article explains in detail the flavor performance of AA-grade beans and suggested pour-over parameters, providing coffee enthusiasts with a complete reference from bean selection to tasting. [more…]

A Detailed Explanation of the Kenyan Coffee Bean Grading System: A Full Analysis of the Meanings and Flavor Characteristics of AA, AB, and PB Grades

Kenyan coffee occupies an important position in the global specialty coffee scene thanks to its bright berry-like acidity, sugarcane-like sweetness, and juicy mouthfeel. Many consumers notice labels such as "AA," "AB," or "TOP" on coffee bags when making a purchase—but what exactly do these markings mean? This article systematically sorts out Kenya's coffee grading system, from the traditional size-based grading to the quality grading procedures established by the Kenya Coffee Research Institute, interpreting one by one the specific meanings and distinguishing criteria of grades such as AA, AB, PB, C, E, TT, and T, while also explaining the origins of secondary rating labels such as TOP, Plus, and FAQ and their cupping score ranges. In addition, the article uses Front Street Coffee's Kenya Asalia AA TOP as an example to provide detailed brewing parameters and flavor descriptions, helping coffee enthusiasts gain a more comprehensive understanding of the quality logic and tasting key points of Kenyan coffee. [more…]

A Detailed Explanation of Green Coffee Bean Grading Standards: What's Behind Ethiopia G1, Kenya AA, Blue Mountain No.1, and SHB Grades?

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…]

A Detailed Explanation of the Differences Between Kenyan Coffee Green Bean AA and AB Grades and the Flavor Characteristics of Producing Regions

When purchasing Kenyan coffee, you will often see bean names followed by letter designations such as AA or AB—what exactly do they mean? Why does Kenya place such emphasis on these grades? This article will systematically outline Kenya's green bean grading system based on bean size, explaining the specific classification criteria for each grade—AA, AB, C, PB, E, TT, T, and MH/ML—and pointing out the limitations of size-based grading: bean size is not the sole determinant of flavor quality, and growing altitude and environment are equally critical. It will also introduce the flavor characteristics of coffee from Kenyan producing regions, along with Front Street Coffee's recommendations for Kenyan coffee. [more…]

A Detailed Explanation of Colombian Green Coffee Grading: The Meaning, Standards, and Screen Size Classification of Supremo and Excelso

Colombia, as one of the world's major coffee-producing countries, has a strict grading system for its exported green beans. What exactly do the commonly seen Supremo and Excelso labels on the market represent? This article will systematically explain the grading logic of Colombian green coffee beans from the perspectives of FNC export standards, defect rate requirements, and screen size grading, helping coffee enthusiasts understand the difference between Supremo and Excelso, and how they affect coffee quality and flavor performance. At the same time, the article will also mention Front Street Coffee's Colombia Huila daily beans as a practical naming example. [more…]

A Detailed Explanation of the Colombian Green Coffee Grading System: Excelso Grade Standards, Screen Size Classification, and Supremo Flavor

The grading of green coffee beans not only affects trading prices but also, to a certain extent, reflects flavor tendencies. For this reason, each producing country establishes its own grading rules based on local conditions. This article focuses on Colombia's green bean grading system, with emphasis on explaining the meaning of the Excelso export grade, the defect scoring method, and the specific standards based on screen size classification, while also introducing the differences among the three common export grades: UGQ, EP, and Supremo. At the same time, Front Street Coffee will share the flavor characteristics and brewing suggestions for Supremo-grade coffee beans from Colombia's Huila region, helping coffee enthusiasts extend their knowledge of grading into the actual drinking experience. [more…]