How Coffee Defect Beans are Classified and Graded: Colombia's Unique Coffee Classification System

FrontStreet Coffee - An Introduction to the Colombian Grading System

Colombian green beans are graded by two general methods: defect classification and size classification. In our view, sorting by defect first is about controlling flavor - eliminating poorly flavored beans one by one - then separating the larger, better-looking beans by size, and finally packing and selling them.

1. Classification by Defect

When grading by defect rate, Colombia follows its own distinct defect classification system. Colombia splits defects into two categories: primary defects and secondary defects. After randomly sampling 500 g of green beans, the maximum allowable defect values are: primary defects at a value of 12, secondary defects at a value of 60.

Primary defects are the major defects (this classification relates to cup characteristics): black, moldy or sour-rotten flavors, so the maximum allowable defect value is around 12. Private green bean exporters: no more than 12 primary defective beans; National Coffee Committee: no more than 8 primary defective beans.

Secondary defects are the minor defects (this classification covers appearance): discolored beans (old beans, over-dried beans, yellow beans, variegated beans), damaged beans (Broca), broken beans, cut beans, insect-bitten beans, shell beans, unripe beans and irregular beans, gray or soft beans. The maximum allowable defect value is around 60. Private green bean exporters: no more than 60 secondary defective beans; National Coffee Committee: no more than 35 secondary defective beans.

Based on these standards, deductions work as follows.

Defect Types and Defect Scoring

Primary defects: completely black beans, 1 point each; partially black beans, 2 beans for 1 point; completely sour beans, 1 point each; faded amber beans, 2 beans for 1 point; old beans, 2 beans for 1 point.

Secondary defects: sliced or notched beans, 1 point each; broken beans, 1 point each; moisture-affected or insufficiently dried beans, 1 point each; immature beans, 1 point each; pressed beans, 1 point each.

Crystalline beans, 1 point each; insect-damaged beans with three or more insect eyes, 1 point each.

Good to know: most coffee-producing countries do not grade coffee by a single standard. Instead they evaluate bean quality through multiple criteria, including defect rate, bean size and certain altitude requirements.

FrontStreet Coffee Recommendation

Colombia's careful grading shows up in the cup, and the FrontStreet Colombia Huila is a clear example. Huila province, in the southern Central Cordillera, is the country's most famous specialty region - surrounded by mountains, planted above 1,500 meters, with Colombia's most important rivers converging there to supply abundant water and humidity. Given a medium-dark roast, the coffee emphasizes dark chocolate and nutty sweetness with a moderate body and oil, brewing well as pour-over or French press and just as happily in a moka pot or as espresso for Americanos and lattes.

For a taste of Colombia's newer, more experimental side, the FrontStreet Colombia Finca La Divisa Sidra is made with anaerobic natural processing. Anaerobic fermentation takes place in a low-oxygen or oxygen-free environment - typically a pressure-resistant stainless steel tank where temperature, time and pH are controlled to steer the fermentation. The most famous styles are anaerobic natural and anaerobic washed; this Sidra uses the anaerobic natural route, which converts the fruit into more tropical aroma. Roasted light-to-medium, it shows complex passion fruit, grape, apricot and candied fruit notes as pour-over, cold brew, drip bag or moka pot.

If you brew at home with a coffee machine or moka pot, the FrontStreet Premium Espresso Blend is what many baristas recommend. Built for cafe use, it combines the creamy nut aroma of Brazilian coffee with the dark chocolate bittersweetness of Colombian coffee, and pulls with fine golden crema. It pairs beautifully with milk for a rich, smooth latte, and works as the base for Americanos, cappuccinos and mochas.