Scheme 1. Comparison of the programmed pruning cycle with the traditional method
17. HARVEST, DRYING, PROCESSING AND STORAGE OF CONILON COFFEE
Recommendations for the production of quality coffee should be followed by producers, because this offers the grower sustainability, security of market,
added value and the opening of new markets.
Production of good quality coffee begins when the farmer correctly follows the recommendations, which starts in the choice of variety and extends through the running of the plantation, cultivation and phytosanitary practices, in nutrition, in irrigation, in pruning, and principally at harvest and in post-harvest processing (RIOS, 2003).
Proper use of improved varieties, fertilization, irrigation, pruning and cultural and phytosanitary practices provides better development of coffee beans, good uniformity of maturation and a lower percentage of sterile cherries; and these characteristics have a positive affect on the amount and quality of the final product.
We recommend the following procedures for harvesting, drying, processing and storage, aiming to produce quality coffee (FONSECA et al., 1995; FERRÃO et al., 2001; DE MUNER et al., 2003; RIOS, 2003; Fonseca et al., 2007; Fonseca et al., 2011).
17.1. HARVEST AND PREPARATION
A harvest done well is essential to produce quality coffee. Before starting the harvest, the producer should be organized, making sure he has purchased sieves, tarps, sacks, and has cleaned and repair yards, warehouses and machines.
The harvest should begin when more than 80% of coffee is already ripe, and the fruits have acquired a cherry color (Figure 24).
The coffee must be spread out on screens or tarpaulins, and should never be spread directly on the ground.
After harvesting, and while still in the field, coarse impurities such as sticks and leaves should be removed.
In a harvest done well, fruit should not be left on the plant or on the soil.
Failures such as these promote the increased incidence of coffee berry borer in the next crop.
Transport the harvested coffee to the drying yard or dryers every day to prevent fermentation.
Figure 24. Crop with 80% mature fruit.
Do not let the freshly harvested coffee form heaps in the yard.
If possible, use the washer / separator to remove impurities and separate the ripe fruits from green cherries.
For the production of processed coffee by the wet method, the ripe and green cherries are passed through the pulping machine for the separation and removal of skin and pulp from the fruits, preferably on the day of harvest.
17.2. DRYING
17.2.1 Drying on patios/yards
If the choice is to dry the coffee naturally in the sun, the coffee should be spread into thin layers, 3-5 cm thick, spreading with a rake, an average of ten times per day, orientated east-west, to accelerate drying and prevent fermentation of the cherries (Figure 25).
Before the coffee is half-dry, it is not to be heaped or covered with canvas. In the early days of drying, rake the coffee into windrows up to 5 to 10 cm high every afternoon in the direction of the slope of the patio. As days pass, the windrows may be increased to a thickness of 20 to 30 cm, until the coffee is half-dried.
After the half-dry point, the coffee must be covered in the evening, so that there is uniformity of drying.
If rainfall occurs at night, move the windrows around until the entire patio is dry, when the coffee should be spread again. If rain continues, rake the windrows 3-4 times a day.
Drying is complete when the coffee reaches 12% moisture content.
17.2.2 Machine-drying
The coffee crop at harvest has high humidity. Thus, it is recommended to be subjected to three to four days pre-drying before being passes on to the dryer. If this is not possible, the dryer should be adjusted so that the temperature at the start of drying is lower, and with more ventilation.
To avoid reducing the quality of the coffee, drying should be performed
with an indirect fire source. The dryer should work at full load and withhomogeneous product lots. If wood is used as fuel, it must be very dry.
The temperature in the mass of coffee must be checked and should not be greater than 60° C.
When the coffee reaches about 17% moisture, the dryer should be
Figure 25. Coffee drying on cement patios or on suspended platforms.
Figure 26. Drying in a mechanical dryer, with the use of an indirect fire.
turned off for the coffee to “rest.” So during this phase, it reaches the desired moisture content for storage. Care must be taken not to dry the coffee excessively, because this leads to weight loss and breakage of the beans during processing (Figure 26).
17.3. CHERRY PROCESSING
If the producer has appropriate infrastructure and wants to make
processed coffee, it should first be sorted into lots by immersion in water:floating fruit (unripe), and the green and cherry fruits, which sink. The
former batch should go directly to drying. The green and ripe cherries go to the pulper, and are then rinsed and spread out for drying, being placed in thicker layers and continuously turned, until dry (Figure 27).
The pulped cherries, can be partially demucilaged, and must be spread in layers 2-3 cm thick in the yard or patio and turned up to 20 times per day. This procedure allows rapid drying. It is recommended to protect this type of coffee from rain and dew (Figure 27).
The production of processed coffee provides the following benefits:
improved final product quality, reduced time, and reduced labor and drying
times, increased assurance of market and price.
17.4. STORAGE
Figure 27. Coffee processing using a technique of cherry hulling for the improvement of the quality of the final product.