Coconuts
| Infobox on Coconuts | |
|---|---|
| Example of Coconuts |  |
| Facts | |
| Origin | - |
| Stowage factor (in m3/t) | - |
| Humidity / moisture |
|
| Ventilation | - |
| Risk factors | - |
Coconuts
Contents
Description
Postharvest cooling, handling and storage of (fresh) Coconuts
| Freshness facts | |
| Optimum carrying temperature | 0°C to 1,5°C (see text) |
| Highest freezing point | -0,9°C |
| Acceptable products temperature at loading
into container |
Max. 2°C above carrying temperature |
| Optimum humidity | 75% to 85% |
| Ventilation
(air exchange) settings for containers |
5 m 3/hr |
| Storage life | 2 months |
| Climateric/non-climacteric | Non climacteric |
| Ethylene production | Very low |
| Ethylene sensitivity | There are no reports of sensitivity to ethylene |
| Modified/controlled atmosphere | - |
| Potential benefits | - |
| Availability | On demand |
Harvesting and handling
Coconuts are the stone fruits of the coconut palm which flourish best in tropical coastal regions (salt spray). The native habitat of the coconut palm is not known with certainty because coconuts can float for considerable distances in seawater without losing their ability to germinate. As a result, coconuts palms are now to be found on tropical beaches worldwide.
50 - 120 fruit may be harvested from a single coconut palm. Each fruit weighs 1 - 2.5 kg.
A longitudinal section through a coconut reveals the following structure: the coconut is enclosed in a leathery, glossy outer skin (exocarp), which is of a yellow-green to yellow-brown colour and is watertight. Under the exocarp is a spongy, fibrous husk (coir) or mesocarp, which is 4 - 6 cm in thickness. This layer corresponds to the flesh (pulp) of other fruit. The fibrous husk is removed from the hard nut with a spike. The fibres are processed to produce carpeting, mats and the like. Removal of the coir reveals the familiar coconut. The outer layer of the coconut is a brown, very hard endocarp, approx. 0.5 cm thick, which is a rounded, triangular stone, the blunt end of which has three "eyes", i.e. germ pores set in pits.
Moving inwards, the following layer is the solid endosperm, an oily layer 1 - 2 cm in thickness which is protected by a brown seed coat and, once dried, yields copra. The seed coat contains antioxidants which protect the oil-rich seed from atmospheric oxygen so preventing it from becoming rancid (oxidative rancidity).
The kernel is hollow and 95% full of clear coconut milk (liquid endosperm).
Coconuts which are intended for transport have generally already had the outermost two layers removed.
Young coconuts are harvested 6 to 9 months after flowering, as the nut approaches full size and the skin is still green and the short stem on the top of the individual coconuts that originally held the male flowers (‘rat-tail’) becomes half green and brown. In immature nuts, the skin surface around the calyx (cap) on the top of coconuts is creamy-white or a whitish yellow. When the area surrounding the cap is green the coconut is regarded as mature and is 10 to 12 months old. At maturity the skin begins to change from green to yellow then brown and the ‘rat tail’ is entirely brown.
Coconuts which are 6 - 7 months in age contain the most milk. As ripening continues, the coconut milk solidifies to form white kernel or flesh (copra). Once all the milk has solidified, the flesh takes on a soapy flavour, becomes inedible and is worthless.
Maturity, size, freedom from blemishes, cracking, freedom from fibre of husked coconuts, and wet mouldy eyes are major quality characteristics.
Fresh coconuts are mainly eaten raw. Further coconut products: sterilized coconut milk for alcoholic drinks (e.g. pina colada), desiccated coconut, coconut fat, coconut oil, coconut fibres, copra.
In order to ensure safe transport, bags with de-husked coconuts must be stowed and secured in the means of transport in such a manner that they cannot slip or shift during transport. Attention must also be paid to stowage patterns which may be required as a result of special considerations, such as ventilation measures.
Coconuts are extremely sensitive to pressure, impact and jolting/vibration. Incorrect handling quickly results in smashed and burst fruit, which are worthless and also give rise to mould and rot on adjacent, unblemished nuts. There is also a risk that the nuts will burst under excessive stack pressure. Hooks must not be used.