How to read a coffee grading report?

A coffee grading report is the technical blueprint of a coffee lot. It provides an objective analysis that allows roasters and traders to understand exactly what they are buying before a single bean is roasted. When you look at a report, the first thing to check is the physical inspection section. This will list the number of primary and secondary defects found in a 300-gram sample. Remember that primary defects, like full black beans or stones, are zero-tolerance items in specialty coffee. If the report shows even one, the lot is disqualified from specialty status.

Next, look for the screen size information. This tells you the physical dimensions of the beans. A report might show a distribution, such as "80% screen 18, 20% screen 17." This indicates the uniformity of the lot. High uniformity is a positive sign, as it suggests the coffee will roast evenly. If the report shows a wide range of sizes, it may indicate that the coffee will require more careful roast management to avoid uneven development.

Then, examine the sensory evaluation, often summarized by the cupping score. This is the result of a professional cupper evaluating the coffee based on the SCA 100-point scale. The report will break down the score into categories like fragrance/aroma, flavor, acidity, body, and aftertaste. This section is where you get a sense of the coffee's character. A score of 80 or above is the baseline for specialty coffee, with higher scores indicating more complexity and distinctiveness.

Finally, look for additional data points like moisture content and water activity. These are critical for the longevity and stability of the green coffee. Specialty coffee should typically have a moisture content between 10% and 12%. If the moisture is too high, the coffee may be prone to mold; if it is too low, it may taste dry or papery. These technical specs are the "hidden" part of the report that ensures the coffee is safe and stable for storage.

In practice, reading a grading report is about understanding the potential of the coffee. It is a tool for risk management and quality assurance. By learning to interpret these reports, you gain a deeper understanding of the effort that goes into producing high-quality coffee and can make more informed decisions about the beans you choose to brew.