In general, refrigerated commodities may be divided into two distinct categories:
Many chilled cargoes (e.g. fruit) are regarded as a "Live" cargo since they continue to respire post harvest and as such are susceptible to desiccation (wilting and shriveling). This is not the case with commodities such as chilled meat or cheese.
The minimum fruit carriage temperature is usually no lower than -1.1°C (30°F).
Frozen cargo is regarded as "inert" and is normally carried at or below -18°C (0°F).
However, both categories are highly perishable and require care in handling to ensure arrival in optimum condition. In chilled commodity transportation, the ventilators are normally left in an open position, with a limited number of exceptions (e.g. meat, chocolate, film, chemicals, dairy products, and controlled atmosphere shipments).
Some cargoes may require controlled humidity (e.g. flower bulbs). It should be remembered in such cases that many refrigeration units are only capable of reducing humidity within the cargo space and the settings should be applied accordingly.
|
