What a difference a few years makes when dealing with transporting perishable food products. Trailer floors today are made of solid aluminum. It wasn't too long ago that trailers had ribbed aluminum floors. Why? So the blood from fresh meat had a place to drip into.
"The solid floors came out three or four years ago because everything now is either packaged or sealed with Cryovac plastic food packaging," says Bill Behrmann, vice president of Madison, IL-based Lancer Distributing, a subsidiary of OH Logistics. "The new floors are a lot more efficient and a lot more solid. They hold the temperature better."
This colorful change is just one example of how the industry is focused on the integrity of the cargo more than ever before. Food safety continues to be a top concern for grocery wholesalers and foodservice distributors. Monitoring the temperature of food in transit and ensuring HACCP regulations are met remain key.
The most common reefers are single-temperature units, where one temperature is maintained for the entire trailer. Multi-temperature systems allow companies to divide the trailer into several compartments. In its simplest form, think of a refrigerator/freezer combination with a compartment for perishable products and another for frozen, such as in a kitchen refrigerator. Depending on the food cargo, more temperature set points may be needed, resulting in three refrigerated compartments, each held to a precisely-controlled temperature.
"Multi-temperature transport refrigeration units offer enhanced food quality and safety by controlling temperature at the optimum level for a variety of products," says Jerry Duppler, product manager, trailers, for Thermo King Corp. in Minneapolis.
Two- and three-compartment systems allow operators to select optimum temperatures for diverse products such as ice cream, fresh produce and bananas—all in the same truck or trailer. These systems have contributed greatly to improved logistics and enhanced food safety and quality control for many companies in the foodservice and food distribution industries."
The new generation of temperature controllers that runs the equipment is much more sophisticated and is much easier for the driver to use, according to Ignacio Aguerrevere, director of marketing and product development for Carrier Transicold, Syracuse, NY.
"We have temperature sensors within the reefers that determine the supply air temperature, the return air temperature. We can also have remote sensors which could be placed wherever the customer decides to place those sensors. All of that information is used for the reefer to determine the operating conditions."
For a number of years, Carrier has offered its Genesis multi-temperature system. The units use conventional mechanical refrigeration technology. Last year, Carrier introduced the Vector 1800MT multi-temperature system which uses a patented Deltek hybrid diesel-electric technology. The system is entirely electric, using a diesel engine to power the generator.
While basic technologies used in transport refrigeration systems are essentially unchanged over the past five years, according to Thermo King's Duppler, significant developments have occurred in the following areas:
- Improved emissions performance of systems and other solutions to address environmental regulations;
- Improved fuel efficiency;
- Enhanced user interface systems for improved performance and ease of use; and
- Expanded use of data collection and data management aimed at enhanced food safety and food product integrity.
"Food safety has been enhanced by the use of microprocessor control systems with increased capability for precise temperature control and data recording systems for documentation of food temperature throughout the distribution chain," he says. "Satellite and other wireless technologies are being employed to monitor food cargo and transmit temperature and operation data throughout the transit cycle."