The journey from bean to cup is meticulous and detailed. It is not as simple as harvesting, processing and importing green. In fact, green coffee undergoes various grading to determine the quality of the bean. In this blog, we will dive into what coffee grading entails, how it works, country-specific grading, and why it is important.

What is coffee grading?

Coffee grades define the level of quality and is a quality classification, entailing a series of technical assessments to determine these qualities, value and classification. A coffee grade helps sellers and buyers understand the quality benchmark with each other. There are different grading methods for different regions around the world but ultimately the goal is to identify coffee beans with superior characteristics such as size, density, and moisture content. Factors that are considered when grading coffee are the bean size, colour, weight, shape, and if there are defects present.

Grading Process:

Here are the steps and factors involved with coffee grading:

Sampling: The grading process will generally start by sampling, where graders select a representative sample from a larger batch of green coffee beans which should be an accurate reflection of quality of the overall quality of the batch.

Defect Analysis: A vital part of the grading process is the visual analysis of any defects that may be present. Common defects include:

• Quakers: Underdeveloped coffee beans

• Broken Beans: Fractured beans that can lead to uneven roasting

• Foreign Matter: Any non-coffee material found among the beans, such as twigs or stones

If these defects are not identified, it will drastically affect the coffee’s overall score, quality and classification.

Moisture Content Analysis: Moisture content is crucial for determining the shelf life and flavor of coffee. Moisture meters are used to make sure that the beans have an optimal moisture level which is generally between 10-12%. This is important because if the moisture is too high, it can lead to mold, while low moisture can affect flavor.

Screen Size Classification: Beans are sorted by size using a series of screens with varying hole sizes. Larger beans tend to produce better-quality coffee, so size is an important factor in grading.

Screen-size is a traditional method of grading coffee beans and is down by sifting coffee through metal sheets with progressively smaller holes. Usually, the size of the holes are measured in 1/64 of an inch.

Cupping: The next step in the grading process is cupping. A familiar step to assess and evaluate the attributes of the coffee. This sensory evaluation helps determine the coffee’s overall quality and potential.

Country-specific coffee grading:

It is important to discuss country-specific coffee grading as there is no universal coffee grading system, which can be a little bit confusing. Some examples and terminology are:

Brazil: uses a numbering system where higher numbers indicate larger beans. It is based on the standards set by the Brazilian Official Classification (COB).
Brazil was the first country in the coffee belt to have a standardized coffee bean grading system from 1836 onwards.

Colombia: uses EP for preparation, and Excelso and Supremo for size grades. Grades:

• Usual Good Quality (UGQ): used to describe Colombian beans that are of decent quality with minor defects or size variation.

• Excelso: A grade where at least 95% of the beans are screen 14 and at least 50% screen 15.

• Extra: these beans are also considered high quality, but they might be slightly smaller than Supremos.

• Supremo: A grade where at least 95% of the beans are screen 17 and 100% is above screen 14.

Central America: Uses designations like SHB (Strictly Hard Bean), HB (Hard Bean), and SHG (Strictly High Grown) to indicate higher quality based on altitude and density.

Indonesia: Uses a combination of defects and size, with Gr. 1 being the most common imported grade.

Kenya: uses a size-based system, with AA being the highest quality. Grades:

• Kenya E (Elephant Bean): Largest size of Kenyan coffee beans.

• Kenya PB (Peaberry): Instead of the usual expected two flat-sided beans, a single round bean develops within this coffee cherry.

• Kenya AA: Indicates large beans and are renowned for their bright acidity.

• Kenya AB: Combines beans of slightly smaller size than AA.

• Kenya C: Smaller bean size and may have minor defects compared to the higher grades.

Ethiopia: uses a number-based system from Grade 1 – Grade 5. For further information, we have actually already written a blog around the Ethiopian Grading System.