Pineapples

Infobox on Pineapples
Example of Pineapples
Freshness facts
Optimum carrying temperature	10°C to 13°C (mature green) 7°C to 10°C (turning) 7°C (ripe)
Highest freezing point	-1,1°C
Acceptable product temp. at loading into containers	Max. 2°C above carrying temperature
Optimum humidity	90%
Ventilation setting for containers	25 m³/hr
Storage life	3-4 weeks (mature green/turning)
Climacteric / non-climacteric	Non-climacteric
Ethylene production	Low
Ethylene sensitivity	Low
Modified / controlled atmosphere	5%-10% CO2; 2%-5% O2
Potential benefits	Increased CO; slight to moderate Reduced O2; slight
Availability
	On demand

Pineapples

Harvesting and handling

The fruit is harvested while still firm (two-thirds ripe). In most varieties, the degree of ripeness of the fruit is clear from the yellowness of the skin. However, a pineapple may be fully ripe while still green on the outside. If one of the inner crown leaves can be pulled out easily, the pineapple is fully ripe. Pineapples intended for shipping are harvested when green, while those intended for immediate eating are harvested in the semi-ripe state and those intended for canning in the ripe state. Since pineapples are a non-climacteric fruit, they should not be cut before ripening begins if a good flavour and quality are to develop.

The pulp generally only reaches its full flavour if the fruit is left to ripen on the plant. The pale yellow to golden pulp is high in sugar and acids and has an excellent flavour (eating, luxury or dessert fruit).

Only sound fruit provided with fungicidal paste on the cut stalk may be approved for transport. Pineapples which are bruised prior to transport must be rejected, as they start to rot very rapidly.

Bruising, due to impact damage, is a major problem during harvesting, packing and shipping of pineapples. This injury is normally confined to the impact side of the fruit, and the damaged flesh appears slightly straw coloured.

Pineapple fruit must have a desirable size and shape, with flat ‘eyes’ (individual fruitlets) and crown leaves that look fresh and are deep-green. High shell colour is not always a good measure of sweetness. Negative characteristics include: dry, brown crown leaves; dull, yellow skin appearance; presence of mould on the surface or cut stem; and fruit having an unfirm feel.

The packaging must allow sufficient ventilation of the pineapples, since stagnant air around the pineapples encourages mould growth. This is ensured by perforations in the sides and the top and bottom of the described cartons.

Cooling and storage

At temperatures > 10°C, the crown leaves have an increased tendency to bolt. Bolted crown leaves impart a tired appearance to the fruit and diminishes its value. In addition, the tendency to fruit rot (black rot) also increases, often occurring as butt rot above the stem but also arising in the crown.

Susceptibility to chilling damage reduces as ripeness increases.

Exposure of pineapples to temperatures below 7°C results in chilling injury. Ripe fruits are less susceptible than unripe or partially-ripe fruits. Symptoms include dull green colour when ripened (failure to ripen properly), water-soaked flesh, darkening of the core tissue, increased susceptibility to decay, and wilting and discoloration of crown leaves.

Mixed loads

Pineapples readily absorb off-odours from avocados and green peppers. They are neither sensitive to ethylene nor great producers of ethylene. Pineapples can be shipped with citrus fruit provided the shipping temperature is suitable for both products.

Cautions

O₂ below 2% can cause off-flavours. CO₂ above 10% can also cause off-flavours. Less mature fruit are more susceptible to chilling injury and should not be kept below 10°C while ripe fruit may be held as low as 7°C.

Storage disorders

Aspergillus rot, Bacterial soft rot, Black rot, Botryodiplodia rot, Core rot, Chilling injury, Internal browning, Rhizopus rot, Yeasty rot.