Sugar content should be assessed in the field prior to harvesting to ensure adequate sugar development. A minimum of 10 % is generally required although this may vary with the market. Sugar content is not always related to the colour stage as agronomic and production factors will affect sugar development. For the export market where sea-shipment for seven to fourteen days is used, fruits should be harvested at CS1, where the fruits show no yellow colour development on the eyes (ensuring that checks have been made on the sugar content). For airfreighted shipments, although generally cost prohibitive, harvesting can be carried out at CS2 to CS3. Those harvested at more advanced stages are more susceptible to mechanical damage and over-ripeness. Fruit maturity can also be assessed on random samples by determination of the flesh condition. This is carried out by slicing the fruit horizontally at the point of largest diameter. In fruit for sea-shipment export the fruit should show limited development of translucent areas. Where more than half of the area is translucent, the fruit is considered beyond optimum maturity. Pineapples harvested by hand are snapped from the stalk using a downward motion. The fruit should be placed in field crates and while in the field, left in shaded conditions. Collection in the field and field to pack house transport using sacks or bags will cause mechanical damage and increase the level of rejection. On arrival at the packing facility, the stems and the crowns should be trimmed to 2 cm (0.5") and 10 cm (4") respectively. Out grading should be made of all fruits which are undersize, oversize, over-ripe, under-ripe (depending on the market requirements), damaged, bruised or show fungal or insect damage.

Export grading and packing

For reduction of post-harvest disease incidence, the fruit should be treated, by dipping or spraying, with a solution of Dowicide A (sodium 2-phenylphenolate) at a concentration of 7 g per litre of water. Size grading and packing should be carried out immediately after treatment. Pineapples are packed according to the stage of ripeness and the size of the fruit. Fruits in individual cartons should be the same size, resulting in a range of counts.

Accepted counts are as follows:

6 count - 1.75 kg fruit (3.8 lb)
12 count - 1.25 kg fruit (2.7 lb)
12 count - 1.00 kg fruit (2.2 lb)
20 count - 0.75 kg fruit (1.6 lb)

A full-telescopic two-piece fibre-board carton with internal dividers between the fruit is used. Top and bottom ventilation, in addition to side vents are required, particularly where sea-shipments in break bulk are used. Where staples are used in carton construction, care should be taken to ensure complete staples closure to prevent fruit damage. The preferred method of packing is to place the fruit vertically on the base, and then to place dividers between the fruits to prevent rubbing and movement. With some cartons, this is not possible and fruit are laid horizontally in alternating directions; where two layers of fruit are packed, a layer of card is required between the layers. Fruit are normally packed to a net weight of 10 to 15 kg (22 to 33 lb) depending on the carton and the market. High value small pineapples may be shipped in some instances at 6 kg (13 lb), whereas the large fruit in some cases may be packed up to 20 kg (45 lb).

Carton internal dimensions

27 x 48 x 34 cm (10.6" x 18.9" x 13.4")
20 x 51 x 34 cm (7.9" x 20" x 13.4")

Source: http://www.pnbkrishi.com

Storage and transportation

Where sea-shipment is to be used, the fruit should be harvested on the day prior to shipment. Green fruit should be stored at 10°C, 85 to 95% relative humidity, and under these conditions, should have a storage life of 2-3 weeks. This will be dependent on the sugar content and the agronomic conditions during production, in addition to the handling and storage procedures. Where exports are made by airways with fruit harvested at more advanced stages of maturity, pre-export storage can be used and the suitable storage temperature decreases to 7.5°C, 85 to 95% relative humidity.

Potential post-harvest losses

Losses in pineapples during air-transport are minimal if careful handling is employed. On sea-shipments and long-term storage however, the fruits are more susceptible to post-harvest losses as a result of handling, control of temperature and disease incidence.

Mechanical damage

Bruising or puncturing caused by poor handling, dropping or abrasion, will result in localised areas of softening and development of secondary microbial infection.

Low temperature

Sensitivity to chilling injury is related to the level of ripeness of the fruit. Storage of green fruit (CS 1) should be at 10°C, 85 to 95% relative humidity; storage for extended periods below this temperature will result in chilling injury shown by incomplete colour development, wilting and darkening of the flesh and peel. Pineapples with 25% yellow eyes can be stored for 1-2 weeks at 5° to 7°C; critical temperatures may be dependent on the production area and growing conditions.

Pathological factors

• Black rot

Black rot caused by Ceratocystis results in a black watery rot of the flesh and a thin brittle skin. Infection usually occurs through the cut stem or through damaged areas, but can generally be controlled by prompt treatment with either Dowicide A or Thaibendazole. Black spot or brown spot caused by Penicillium funiculosum and Fusarium moniliformae results in browning and sinking of the eyes and browning of the internal fruitlets. Incidence is not usually detected until the fruit is cut. The diseases are believed to be caused by mite damage in the field allowing entry of the fungi. Pre-harvest spraying regimes are required to control the mite population.

• Endogenous brown spot

Physiological disorder characterized by watery spots, eventually coalesce and turn brown. The incidence is found in certain varieties and production areas and is generally enhanced during long term storage.