Unraveling the AA, AB, PB, and Other Grading Systems
【Coffee Trivia】Unraveling the AA, AB, PB, and Other Grading Systems
2023-09-14Coffee Trivia
Have you ever come across abbreviations like G1, AA TOP, AB TOP, etc., on coffee shop menus? For those new to specialty coffee, these terms might be confusing, leaving you uncertain about their meanings and flavor profiles.
Let's dive into the grading system of Kenyan coffee and uncover its mysteries!
The grading of Kenyan coffee is primarily based on the size of the coffee beans:
- E (Elephant): Here, "E" stands for "Elephant," but it doesn't refer to the Elephant bean variety (Maragogype) within the coffee beans. Elephant beans occur when two seeds grow abnormally and stick together, forming a large bean. E-grade beans have a size of approximately 18 screen (about 6.7 to 7.1 mm) and are relatively rare.
- AA: Beans in this grade have a size of around 17 to 18 screen (about 6.7 to 7.1 mm), making it the most familiar Kenyan coffee grading. However, AA does not necessarily represent the best quality; it merely indicates the size of the beans and does not correlate with flavor. In Kenya, larger beans are generally considered of better quality. (Try the recommended Kenyan AA by Coffee Market.)
- AB: The majority of coffee beans fall under this grade, as it combines A beans with a filter size of 6.80 mm and B beans with a filter size of 6.20 mm. The resulting mixture is labeled as AB, with a size ranging from 15 to 16 screen (about 6.0 to 6.4 mm).
- C: Beans in this grade have a size of approximately 14 to 15 screen (about 5.6 to 6.0 mm), which is smaller than B-grade beans.
- PB (Peaberry): Known as Peaberry in English and "小圓豆" in Chinese, these beans are relatively rare and account for about 10% of all coffee beans. Peaberry beans develop when only one seed matures within the fruit, resulting in small, round beans. Some coffee enthusiasts particularly enjoy the flavor of Peaberry beans, leading to their separate sale.
- TT: These beans are lightweight and not up to the standard hardness of AA and AB beans. They are obtained through air separation machines that sift beans from AA and AB batches. TT beans often have defects and cracks.
- T: These are lighter beans screened from the C-grade beans and may include impurities, damaged beans, or even bean fragments.
MH/ML: Beans in this category are generally considered unsuitable for export. They are mostly overripe coffee beans that fall to the ground, resulting in poorer quality. They make up around 7% of all coffee beans and are primarily supplied to the domestic market in Kenya.
Now that you understand the grading system of Kenyan coffee, I hope it enhances your coffee-tasting experience and adds more enjoyment to your journey into the world of coffee!