Cost of coffee.indd - RISC

processing
D because berries on each stem ripen at different times, only ripe red cherries are selectively
picked by hand every 8-10 days for best quality – this is more time consuming and
expensive because each tree must be visited several times; one picker gathers an average of
75kg per day; stems can be stripped of both ripe and unripe fruit at the same time by hand
or machine – this reduces quality but modern processing can mask the unwanted bitterness
D cherries processed to remove beans from pulp using two alternative methods – dry and wet
dry ‘natural’ method
D this is the oldest, simplest method and requires little machinery but is not suitable in very
wet regions where it rains frequently during harvesting
D involves drying the whole cherry; three basic steps – cleaning, drying and hulling; variations
on how the process may be carried out, depending on the size of the plantation, the facilities
available and the final quality desired
D harvested cherries are sorted and cleaned, to separate the unripe, overripe and damaged
cherries and to remove dirt, soil, twigs and leaves; can be done by winnowing by hand,
using a large sieve and picking out remaining waste; ripe cherries can also be separated by
flotation in washing channels close to the drying areas
D cherries are spread out in the sun to dry, either on large concrete or brick patios or on raised
trestles which increase air flow, reducing drying times
D cherries are turned by hand to ensure even drying; up to 4 weeks before the cherries are
dried to the optimum 12.5% moisture content, depending on the weather conditions
D on larger plantations, with higher production, machine-drying can be used reduce the
process to 3-4 days
D drying is the most important stage of processing, since it affects the final quality of the
green coffee – overdried coffee is brittle and produces too many broken beans during
hulling (broken beans are considered defective beans); poorly dried cherries can spoil by
fermentation
D dried cherries are stored in bulk in special silos until they are sent to the mill where all the
outer layers of the dried cherry, including the parchment, are removed in one step by the
hulling machine to produce green coffee beans
D the beans are sorted by hand or machine to remove stones, damaged beans or bits of pulp
which reduce the price; they are graded into different sizes – larger beans fetching higher
prices – and bagged
D the dry method is used for about 95% of the arabica coffee produced in Brazil, most of the
coffees produced in Ethiopia, Haiti and Paraguay, as well as for some arabicas produced in
India and Ecuador; almost all robustas are processed by this method
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