Are you paranoid about temperature control?

The cold, hard facts

Refrigerated transport suppliers are obliged by law to abide by health and safety standards and regulations, including, and most importantly, ensuring that the cold chain is maintained from point of loading to point of delivery.

Road transportation is the major mode of conveyance for the vast tonnages of meat, fruit, vegetables, dairy products and other temperature-sensitive products transported daily. Reefers and insulated refrigerated delivery vehicles move vast quantities of perishable food products between processing plants, warehouses, distribution centres and, ultimately, on to the retail trade.

Refrigerated vehicles, unless correctly equipped for specific tasks and properly maintained, reach a replacement date sooner than conventional articulated and rigid vehicles in similar transport operations.

Efficient refrigerated transport is much more than simply fitting a fridge unit to an insulated trailer or van body.
Meeting cold chain standards and their legal requirements demands a thorough understanding of:

  • The product to be transported
  • The correct loading procedures and the optimal temperature at which to transport perishable products
  • The optimal design and specification for trailers or truck-mounted insulated boxes
  • The criteria for choosing a suitable and appropriate fridge unit
  • Optimal location of the evaporator(s) and temperature monitoring probes
  • Unloading procedures
  • Maintenance of equipment
  • Training of schedulers, warehouse personnel (loaders and checkers), drivers and crew
  • Ongoing communication with shippers (consignors), agents and consignees (the recipient of the goods) is equally important.

Where products are transported at different temperatures within the same vehicle, it is imperative that the products and refrigerated truck or trailer are pre-cooled to the required temperature prior to loading.

It is not enough to load the vehicle at ambient temperature and then rely on the refrigeration motor to do the rest. The cooler unit is designed to maintain the correct temperature and not to cool the product to the required temperature during transit.

Keeping refrigeration motors running while the vehicle is being offloaded simply has the effect of pumping the cold air out of the vehicle, allowing warm air to be sucked in.

This may cause the fridge motor to switch to a defrost cycle, resulting in a drop in temperature.

A trouble-free solution to the above is a door switch that automatically switches off the motor when the doors are opened. This effectively reduces the cold air loss, and can be improved further if coupled with a PVC air curtain behind the doors.

Separating dry goods from refrigerated goods will also improve temperature control and reduce cooler unit diesel consumption. There are numerous options available as load dividers, which can be used in conjunction with a multi temperature cooler unit to accommodate almost any combination of temperature band within a vehicle body.

Making certain the air flow is not restricted will maintain optimum air circulation to ensure the vehicle does not have hot spots. A simple way to improve airflow is to stack the product onto pallets.

It is imperative that staff get the correct training so they are fully aware of  and prepared for their duties. Too often a new employee or short-term contractor is asked to do a job they don’t know enough about.

Transporters must choose the right partners and suppliers who will keep them informed and up to date about best practices and opportunities to benefit from new technologies available.

Refrigerated transport plays a vital role in maintaining the cold chain for perishable goods, but very often basic – yet highly effective – procedures are not adhered to, leading to loss of product quality and resultant costs for all those involved. This is according to the MD of Serco Industries, Clinton Holcroft, who says today’s consumer is not only demanding a fair price for fresh and frozen goods, but also expects high quality with a reasonable shelf life.

“Retailers want to avoid being saddled with the loss from returns, as well as the negativity of having a product that is not to the customer’s satisfaction. The resultant trend is that stores – including butcheries and supermarkets – are getting more involved in checking the temperature of a product when it arrives and have the right to reject the load, which may not have been as stringently enforced five or ten years ago. This means more pressure on the transporter to maintain the cold chain correctly,” says Holcroft.

Lizette Conradie, managing director of LMC Express, says that secondary distribution trucks have great difficulty in maintaining temperature because some consignors or consignees take long to load/offload and therefore keep the doors of the reefer truck open for too long. “The industry suppliers often do not make an effort to keep the doors open for as short a period of time as possible, thereby affecting the remaining product in the vehicle,” she states.

Mrs Conradie says that one of the highest cost factors in the refrigerated transport industry is standing time at the client. This includes the fact that some suppliers load trucks only from 7 am until 12:30 pm during weekdays and not at all over weekends.

“Fast ‘n Fresh did a study for Woolworths DC in Johannesburg and established that they could reduce the number of refrigerated trucks required substantially if the Woolworths DC received and dispatched vehicles 24/7. If more suppliers were prepared to do so, the cost of refrigerated transport can be reduced drastically,” concludes Conradie.