Why Do Coffee Bean Grades Differ Between Countries?

Labels like Yirgacheffe G2 and Kenya AA mark the grade of a batch of green coffee, and each producing country applies its own logic. Criteria include the proportion of defective beans, screen size, growing altitude, bean density and processing method, so coffee bean grades from one country cannot be read directly against another's.

Ethiopia is one example. Before the Ethiopia Commodity Exchange was set up, export coffee grades were set by the CLU under the Ministry of Agriculture, based on defective beans counted in each 300-gram sample. Washed lots usually land in G1 to G2, while early sun-dried lots carried more defects and generally fell into G3 to G5, which is why coffee grades need local context.

When buying coffee beans, you often see labels like Yirgacheffe G2 and Kenya AA. Behind these letters and numbers is the logic each producing country uses to grade green coffee quality. Due to differences in history, trade, climate, and terrain, grading criteria vary widely from country to country—some look at defect rates, some measure bean size, and some test altitude and hardness—and they cannot be directly compared across countries. This time, Front Street Coffee sorts through the grading systems of representative producing countries such as Ethiopia, Kenya, Colombia, Jamaica, Costa Rica, Panama, Guatemala, El Salvador, Honduras, and Brazil, helping you understand the reasoning behind green coffee grades.

For more specialty coffee knowledge, please follow our WeChat official account: Front Street Coffee (FrontStreet Coffee)

When buying beans, many people have probably come across names like Yirgacheffe G2 and Kenya AA. Codes such as G2 and AA are actually marking the grade of that batch of green beans. However, countries do not use a unified method for grading green coffee. Below, Front Street Coffee selects several representative producing countries to discuss their green coffee grade standards.

Coffee Grading and Classification

Coffee Bean Grades The evaluation dimensions usually include the proportion of defective beans, screen size, growing altitude, green bean density, and processing method. Because countries differ in historical background, trade demands, climate conditions, and topographical features, it is difficult to use one set of standards to measure them all, nor can grade be determined by altitude alone. Likewise, using a certain grade from Country A to benchmark against a certain grade from Country B is also inappropriate.

1. Ethiopia (graded by the proportion of defective beans)

Before the establishment of the Ethiopia Commodity Exchange (ECX), the country's coffee export grades were set by the CLU department (Cupping and Liquoring Unit) under the Ministry of Agriculture, mainly based on how many defective beans were contained in each 300-gram sample. The specific grading standards are shown in the table below.

Grade Number of Defective Beans (per 300g)

Usually, washed beans fall into G1-G2, while due to the limitations of early sun-drying techniques, naturally processed green beans had more defects and were generally classified as G3-G5. Later, as sun-drying processing methods continued to improve, naturally processed beans can now also achieve G1-G2 grades. After the ECX (Ethiopia Commodity Exchange) was established in 2008, the method changed to combining the physical attributes of green beans with cupping flavor characteristics to assign scores and determine grades.

According to processing method, the ECX divides coffee into unwashed and washed categories, and defines three types:

a. Specialty: few defects, high cupping flavor quality

b. Commercial: does not reach specialty grade, but is higher than the domestic (Local/Domestic) consumption grade;

c. Local/Domestic: coffee with a large number of defective beans (unripe beans), and relatively poorer flavor caused by being out of season or poorly stored.

Among these, specialty and commercial are intended for the export market. Based on the combined score of physical characteristics and cupping flavor, the ECX divides coffee beans into nine grades, with physical characteristics accounting for 40 points and cupping quality accounting for 60 points.

Physical characteristics (40%):

Washed processing: defect count (20%), appearance and size (10%), color (5%), odor (5%)

Unwashed processing: defect count (30%), odor (10%)

2. Cupping quality (60%)

Grade Score Washed Unwashed

Afterward, G1-G3 are cupped again according to SCAA standards to further evaluate flavor performance. G1 and G2 with a total score of no less than 85 are designated Q1; G1, G2, and G3 between 80 and 85 are designated Q2; all G1, G2, and G3 below 80 are classified as G3. Q1 and Q2 are exported as specialty coffee bean grades , while G4 to G9 maintain their original grading and are exported together with G3 as commercial grade.

3. Kenya (graded by bean size)

Kenyan coffee bean grades mainly depend on coffee bean size and are generally divided into eight grades.

E (Elephant Bean) : Here the "E" stands for Elephant, but it is not the Maragogype variety among coffee bean types. It is a bean formed by abnormal development, in which two seeds become intertwined and form what looks like "one bean," and it is considered a defect. Generally, a fruit contains two seeds facing each other, so one side is flat, and these are called flat beans or mother beans. Grade E beans are oversized beans formed when two seeds stick together during growth. Grade E beans are about 18 screen sizes (one screen is 1/64 inch) or larger, and are rare in number.

AA : The size of this grade is about 17-18 screen sizes (about 6.7-7.1 mm), and it is the Kenyan coffee grade most people have heard of. In specialty coffee, this grade is usually called AA TOP, and it is also a bean many coffee shops promote. However, AA does not mean it is the best; it only refers to bean size and should not be confused with flavor.

Front Street Coffee (FrontStreet Coffee) Kenya Little Tomato is graded AA

AB : Most coffee beans fall into this grade. It is called AB mainly because the screen size of A is 6.80 mm and that of B is 6.20 mm, and these two sizes of coffee beans (Grade A and Grade B) are mixed together for sale, so it is called AB. The size is about 15-16 screen sizes (about 6.0-6.4 mm).

C : The bean size is roughly between 14-15 screen sizes (about 5.6-6.0 mm), slightly smaller than Grade B.

PB : The full name is Peaberry, also called small round bean, or male bean. Compared with ordinary flat beans, this is also quite rare, accounting for about 10% of all coffee beans. It is mainly because only one seed develops fully inside the fruit, resulting in a small, round bean. Some people particularly like the flavor of PB, so PB is sometimes sorted out and sold separately.

TT : This type of coffee bean is the light bean screened out from AA and AB beans by an airflow separator. It is usually light in weight, does not meet hardness standards, and also contains broken and defective beans.

T : Lighter-weight beans screened out from Grade C beans, mixed with broken beans and even fragments of shattered beans.

MH/ML : This type of coffee bean is not exported. It is usually overripe coffee that has fallen to the ground, of poor quality, and accounts for about 7% of all coffee beans. It is only supplied to Kenya's domestic market.

There are many other countries that grade by green bean size, such as Tanzania, Rwanda, Colombia, Jamaica, and so on.

4. Colombia

Grade Size Standard

Jamaica

Front Street Coffee (FrontStreet Coffee) Jamaica Blue Mountain belongs to the NO.1 grade, commonly known as Blue Mountain No.1

5. Costa Rica, Panama, Guatemala (graded by green bean hardness)

At the same latitude and in the same plot, the higher the altitude, the greater the temperature difference between day and night, the longer the coffee growing period, the harder the bean, the more nutrients absorbed by the bean, and the more pronounced the flavor compounds.

Grade Altitude

Front Street Coffee (FrontStreet Coffee) Panama Hacienda La Esmeralda Green Label Geisha belongs to the SHB grade, extremely hard bean.

6. El Salvador, Honduras (graded by altitude)

Grade Altitude (El Salvador) Altitude (Honduras)

Front Street Coffee (FrontStreet Coffee) Honduras Sherry is graded SHG

7. Brazil (graded by bean size, defect rate, and cupping score)

Brazil considers that only beans with no defects at all can be NY.1, but beans with no defects at all do not exist. Therefore, among Brazilian green beans, the best is only NY.2.

According to coffee bean size (NY grading method)

According to cupping grade, they are divided into:

Fine Cup (FC), Fine, Good Cup (GC), Fair Cup, Poor Cup, Bad Cup. For example: Brazil Cerrado NY-2 SC-17/18 FC means that in Brazil's Cerrado region, the NY grading method grade is 2, the coffee bean size is 17-18 screen sizes, and the flavor quality is Fine Cup (excellent flavor).

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