To ensure the optimum transportation conditions are achieved for your cargoes, we recommend considering the temperature and humidity within the container and the availability for free flowing fresh air.
Each product has an optimum storage temperature which is the ideal condition for transportation. Generally, this is the coolest temperature a product can withstand before chilling injury or freeze damage occurs.
Chilling injury is the physiological damage to tropical and subtropical products which have been exposed to low but non-freezing temperatures. The most common example of this is the browning of banana skins. Chilling injury can be undetected whilst the product remains in cold temperatures but once the product is returned to natural or ‘room’ temperature, the damage becomes rapidly more apparent.
Products that can withstand cold temperature without suffering from chilling injury can still become damaged when they reach freezing point. This occurs when the cellular structure of the product is ruptured by the expansion of water during the freezing process. The most common example of this is found in products appearing to be water-soaked with damaged structures.
Humidity levels play a crucial role in achieving the optimum condition for cargo during transit. It is therefore important to ensure the correct humidity levels are maintained to avoid commodities shrivelling or excessive water loss.
Please note: the services we provide can only reduce humidity, we cannot increase humidity levels within the container.
Ventilation is crucial when transporting chilled cargoes to prevent damage to commodities through a build-up of carbon dioxide. Products such as pears and apples are susceptible to damage if there is too much carbon dioxide within the container. Damage caused by excessive carbon dioxide levels can be noticed through the discolouring of the internal tissue of fresh produce.
When transporting chilled cargoes, it is also important to consider ethylene production. Ethylene is a hormone linked to ripening/ageing and is produced by all fruits, vegetables and flowers. Although ethylene is necessary for the ripening process of fruit, it can damage other cargo such as green vegetables.
To overcome the potential risks to the condition of cargo during transportation, an open flow of fresh air can be introduced. This can work to minimise carbon dioxide and ethylene levels within the container and increase humidity levels. However, it is important to ensure that vents are not opened too widely to avoid the entrance of excessive water.
Taking these factors into consideration, we recommend the following conditions for the safe transportation of perishable commodities:
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