AA refers specifically to the size of the coffee beans, and this classification applies to both Arabica and Robusta. The fun fact is that “AA grade” is often assumed to mean top quality or premium taste.
Yet, size is only one part of the bigger grading picture. Coffee is also evaluated by defect count, processing method, and increasingly, its cup quality. These grading systems sometimes overlap, which can create confusion, especially for new buyers or consumers.
For farmers, correct grading can mean higher prices and better market opportunities. For buyers, it helps ensure they are sourcing beans that match their needs, whether that means large-screen beans, clean, defect-free lots, or specialty-grade coffees with excellent sensory profiles.
What Is AA Grade in Coffee?
The term AA grade in coffee refers to a size classification rather than a direct measure of quality or flavor. Coffee beans are sorted using a set of sieves, also known as screens, each with small holes of different diameters. The beans are shaken through these screens, and their size is determined by the screen number on which they are retained.
In this system, AA usually means that the beans are among the largest in size, often retained on screen 18 (7.2 mm) and above. Larger beans are generally preferred in the market because they roast more evenly and are often associated with better development potential, though this is not always a guarantee of superior taste.
Arabica Example:
In Kenya, “Kenya AA” is one of the most famous classifications. Beans graded as AA are large, uniform, and highly valued in auctions. However, their reputation comes not only from size but also from Kenya’s stringent quality controls and favorable growing conditions.
Robusta Example:
In India and Uganda, Robusta beans are also classified into AA, A, B, and C categories, with AA being the largest size. While size matters in marketing, Robusta AA may still vary widely in quality depending on defects and processing.
In short, AA is a physical grading category that indicates bean size. It does not automatically mean the coffee is defect-free, specialty, or high in cup quality. Those qualities are determined by other grading systems, which we will explore in the following sections.
Size Grading Systems Around the World
Although the AA grade is widely recognized, each producing country has its own size grading terminology and standards. The principle remains the same, classifying beans by their diameter using screen sizes, but the names and categories can differ between Arabica and Robusta origins.
Arabica Size Grading
- Kenya: Uses AA (screen 18), AB (screen 16–17), PB (Peaberry), and C (smaller sizes). Kenya AA is especially prized in auctions.
- Colombia: Uses Supremo (screen 17+) and Excelso (screen 14–16). Supremo beans are larger, while Excelso may include smaller but still high-quality beans.
- Brazil: Uses the New York (NY) grading system, combining size and defects. Common size terms include screen 17/18 (large) and screen 14/16 (medium).
Robusta Size Grading
- India: Robusta beans are classified into AA, A, B, and C, with AA being the largest (screen 18). India also has premium washed Robustas such as Robusta Kaapi Royale.
- Uganda: Uses similar classifications (AA, A, B, C), with AA as the largest size.
- Indonesia: Robusta beans are often marketed as screen 18, 16, or below, though the AA–C terminology is also used in some regions.
While larger beans (AA or Supremo) are generally more sought after, size grading alone does not determine overall quality. Small beans can still deliver excellent cup profiles, especially in origins with strong quality control systems.
Defect Grading (Quality Standards)
While size grading (AA, A, B, etc.) focuses only on the physical dimensions of beans, defect grading evaluates the overall quality of a coffee lot by measuring how many defective beans are present. Defects can include black beans, broken or chipped beans, insect damage, mold, or foreign matter. Since defects directly affect cup quality, this system is crucial for determining a coffee’s market value.
Arabica Defect Grading
The Arabica Coffee defines grades based on the number of defects in a 300 g sample:
- Grade 1: Maximum total defect value of 11
- Grade 2: Total defect value from 12 to 25
- Grade: 3: Total defect value from 26 to 44
- Grade 4a: Total defect value from 45 to 60
- Grade 4b: Total defect value from 61 to 80
- Grade 5: Total defect value from 81 to 150
- Grade 6: Total defect value from 151 to 225
Specialty Arabica must not only be low in defects but also score 80 points or higher in cup evaluation.
Read the full details here: Standards for Green Coffee Beans: Grading System
Robusta Defect Grading
Many Robusta-exporting countries use the term FAQ (Fair Average Quality) for commercial-grade beans (Grade 4 in the Arabica Coffee Grading System).
For Robusta Coffee, the overall Grading System is common with the Arabica mentioned before.
Categories are often less standardized than Arabica but usually fall into:
- Specialty/Fine Robusta – very low defects, clean cup.
- Premium Robusta – moderate defects, better than FAQ.
- FAQ (Standard Commercial) – higher defect levels but widely traded.
The International Coffee Organization (ICO) and some local boards are working to create stricter definitions for Specialty Robusta, similar to Arabica standards.
Defect grading highlights a key point: a lot of AA beans (large size) may still be classified as low quality if they contain too many defects. Conversely, smaller beans with fewer defects can achieve a higher grade in the marketplace.
Processing & Appearance-Based Grading
Beyond size and defects, coffee is also classified by processing method and bean appearance. This system is especially important because the way coffee is processed after harvesting influences both how the beans look and how they taste in the cup.
Arabica Processing Categories
- Washed (Fully Washed / Wet Process): Produces cleaner, brighter cups; common in Colombia, Central America, and parts of Africa.
- Semi Washed (Wet Hulled / Giling basah): Produces the famous Earthy Coffees; common in Indonesian Arabica coffee.
- Natural (Dry Process): Beans dried in the cherry, giving a heavier body and fruity flavors; typical in Ethiopia and Brazil.
- Honey / Pulped Natural: A hybrid method where some mucilage is left on the bean, creating sweetness and complexity.
Read the full details here: 5 Coffee Processing Methods Explained: From Natural to Honey and Wet-Hulled Flavors
Many Arabica origins use processing descriptors as part of their grading system. For example, Ethiopia exports “Washed Yirgacheffe” and “Natural Sidamo,” which combine origin + processing to signal expected cup profile.
Robusta Processing Categories
- Plantation (Washed Robusta): Fully washed, often producing cleaner and higher-quality cups; India’s Robusta Kaapi Royale is a prime example.
- Parchment: Typically refers to washed Robusta processed similarly to Arabica.
- Cherry (Unwashed / Natural Robusta): Beans dried inside the cherry; more common in mass-market or commercial-grade Robusta.
- Robusta Kaapi Royale (RKR): A premium Indian washed Robusta, hand-picked and carefully sorted, known for its large size and bold flavor.
Appearance also plays a role in grading. Beans that are uniform in color, size, and shape are valued more highly than mixed or uneven lots.
In both Arabica and Robusta, processing labels help buyers understand not only how the coffee looks but also what kind of cup profile to expect, something size or defect grading alone cannot explain.
Cup Quality (Liquoring Grading)
While size, defects, and processing all matter, the ultimate measure of coffee is found in the cup quality. This is where beans are evaluated through tasting, or cupping, to assess their sensory attributes such as aroma, flavor, body, acidity, aftertaste, and balance.
Arabica Cup Quality
- Governed by the Specialty Coffee Association (SCA) cupping protocol.
- Coffees are scored on a 100-point scale, with 80+ points considered specialty grade.
- Categories:
- Specialty (80–100): Clean, complex, and defect-free.
- Premium (70–79): Acceptable quality but with minor issues.
- Commercial (<70): Standard or bulk-grade Arabica.
Cup quality is why smaller beans from Ethiopia or Panama can command higher prices than large-screen beans from other countries. Flavor profile matters more than size.
Read the full details here: Discovering Specialty Coffee: A Journey of Flavor and Quality
Robusta Cup Quality
- Traditionally, Robusta was traded mostly on physical grading (size, defects, FAQ standard).
- Recently, the Fine Robusta / Specialty Robusta movement has gained momentum.
- Evaluated using the CQI Fine Robusta Protocol, which adapts Arabica cupping standards.
- Attributes assessed include bitterness, body, sweetness, cleanliness, and aftertaste.
- Specialty/Fine Robusta typically has fewer defects, improved processing, and a cleaner, more balanced profile compared to commercial Robusta.
Cup quality grading highlights a critical truth: AA size does not guarantee a good cup. A large bean with many defects or poor processing may taste worse than a smaller bean that has been carefully harvested and processed.
How the Systems Work Together
Coffee grading is a multi-layered system, and no single category, whether size, defects, or processing, can fully define a coffee’s overall quality. Instead, these systems work together to provide a clearer picture of what a buyer is purchasing and what a farmer is selling.
Examples in Arabica
- Kenya AA, Grade 1: Large beans (AA) with very few defects (Grade 1). This combination often signals both high quality and excellent cup potential.
- Colombia Excelso, Specialty: Medium-size beans (Excelso) that, despite being smaller, score 85+ in cupping, proving that flavor can outweigh size.
Examples in Robusta
- Robusta AA, FAQ: Large beans (AA), but graded as FAQ due to higher defect levels. Size is good, but quality is average.
- Fine Robusta A, Washed: Medium-size beans (A), carefully processed and low in defects, scoring well in cupping. Even without the AA label, it can fetch a premium price.
These examples show that size (AA) is only one layer of grading. Defect count, processing, and cup quality ultimately determine how the coffee performs in the marketplace.
For buyers, this layered approach helps ensure consistency in roasting and flavor. For producers, it means that improving processing and reducing defects can be just as valuable, if not more so, than producing larger beans.
Conclusion
The term AA grade is often misunderstood as a symbol of superior quality, but in reality it refers only to bean size, and is used for both Arabica and Robusta coffees. While larger beans are often preferred in the trade for their roasting consistency and appearance, size alone does not guarantee better flavor or higher quality.
To truly understand a coffee’s value, buyers and producers must look at all layers of grading:
- Size grading (AA, A, B, etc.) shows the physical dimension of beans.
- Defect grading reveals how clean or flawed a lot is.
- Processing categories explain how beans were prepared and what to expect in appearance.
- Cup quality grading ultimately determines the sensory experience in the cup.
When these systems are combined, they provide a more accurate picture of coffee’s true potential.