Protecting Perishable Foods During Transport by Truck
The object of refrigerating food products is to maintain quality and prolong shelf life by keeping the product temperature at the point where metabolic and microbial deterioration are minimized. Maintaining the desired or ideal holding temperature is a major factor in protecting perishable foods against quality loss during storage and distribution. Quality loss is a function of both time and temperature abuse. Abuse is additive and, even for short periods of time during loading, transit, and unloading, may cause a considerable amount of quality loss by the time the product reaches its destination.
In the past, several methods of refrigerating trucks have been used. These include ice, ice and salt, dry ice, hold-over plate systems, cryogenic systems, and mechanical refrigeration. Today, however, mechanical refrigeration is the predominant type. Trailers refrigerated with cryogenic refrigerants, usually liquid carbon dioxide (CO2) or nitrogen (N2), have been used to some extent over the past three decades, but they are not as popular as trailers refrigerated mechanically.