Unless coffee is processed using the semi-washed method, the beans are still enclosed in their layer of parchment when they leave the wet mill. The moisture content at this point is low enough for the coffee to be stored without risk of rotting. Traditionally, coffee is intentionally stored at this stage for 30 to 60 days.
The traditional practice of holding coffee (known as in reposo) has not been fully researched, although anecdotal evidence suggests that if this step is missed then the coffee can taste green and unpleasant until it has aged further. There is also evidence that this state influences how well the coffee will age once shipped, which is probably linked to the moisture content within the coffee.
At the end of this period the coffee is sold and then hulled to remove the parchment. Up until this point the parchment has provided a protective layer, but it also adds weight and bulk to the coffee, so it is removed to make shipping less expensive.
Hulling is done mechanically in a dry mill (as opposed to a wet mill). Dry mills also usually have equipment to grade and sort the coffee. Onced hulled, the green coffee beans can be passed through a machine that examines the color and rejects any coffee with obvious defects. The coffee can be sorted by bean size using large shaking sieves with varying hole sizes, and finally it is graded by hand.
This time-consuming process is performed at a large table with a central conveyor, or sometimes on large patios, usually by women rather than men. They pick through their allocation of coffee and remove all the defects they can, sometimes within a given time frame controlled by an automated conveyor. This is a slow process, adding significant cost to the coffee, but also massively increasing its quality. it is undeniably a difficult, monotonous job and it is right that high-quality coffees cost more, so that the people who do this difficult work can be better paid.
Bagging
The coffee is then bagged into either 60 kg (132 lb) or 69 kg (152 lb) jute bags, depending on the country of origin. In some cases the bags are lined with a protective material, such as a multilayer polyethylene, to make them resistant to moisture, or the coffee can be vacuum-packed and shipped in cardboard boxes.
Jute has long remained the material of choice because it is cheap, accessible and has little environmental impact. However, as the specialty coffee industry is increasingly concerned with the condition of coffee during shipping and in ongoing storage, new materials are being explored.
Shipping
Coffee is generally transported from its country of origin in shipping containers. These hold up to three hundred bags of coffee, although low-quality coffees are sometimes just tipped into a giant lining covering the walls of the container, as the waiting roaster will process the entire container on the day it arrives. The containers are emptied out like dump trucks into a receiving station at the roasting facility.
Transporting coffee in container ships has a relatively low impact on the environment (certainly compared to other aspects of the coffee industry), and it is also relatively cheap. The downside is that the coffee can be exposed to both heat and moisture that may damage its quality. Shipping is also a complicated process, with bureaucracy in many countries causing roasters huge amounts of stress as containers of coffee sit for weeks or even months in hot, humid ports waiting for their paperwork. As air freight remains both an environmentally unfriendly and financially unsustainable alternative, many in the specialty coffee industry remain frustrated by this aspect of the business.
