Dry Mill and Sorting

‘Dry milling’, which is the final stage in green coffee production, involves removing the last layers of dry skin, sorting and preparing the beans for shipment. The first of these is called ‘hauling’, which is the removal of the dried sheath peeling off the bean, which in the case of coffee that has been washed as described above is known as parchment skin.

The parchment skin is removed from the coffee bean with the help of machines called hullers, which can range from simple millstones to sophisticated machines that gently abrade the coffee.

Bags full of parchment coffee at dry mill
Parchment coffee going into the Haulers
Coffee Sacks being marked at the Dry Mill

Most high quality coffees then go though several machines that sort the coffee by size and density of bean while removing unwanted debris that may have been mixed up with the coffee during drying in the Patios. One of these machines blows the beans into the air, separating the heaviest best that land closest , from the small beans that are propelled the furthest. Another machine is used to shake the beans through sieves, sorting them by size. A vibrating gravity separator can also be used to collect only the densest most flavorsome beans, ready for final sorting.

Color sorting is the trickiest and perhaps the most important of all the sorting and cleaning. Most high quality coffees are color sorted by hand, in Central America, often by teams of women. Keen eyes pick out discolored or defective beans leaving only the best for packaging. We are lucky enough to have one of the best groups of sorting women at our mill – SuBeneficio. Above is a picture of them in action. The coffee is then stored in Grain Pro – a multi-layer plastic bag made to preserve freshness and aroma for longer keeping our coffees at their best.

The gravity separator: coffee beans being sorted by weight and density
The beautiful women sorting our coffee to perfection
Green coffee is then stored in Grain pro bags for maximum freshness