Collaborative efforts across the cold chain ensure that produce is presented to shoppers in the freshest possible condition. One of several key activities is that of loading - the placement of palletized fresh produce aboard transport vehicles. Trained personnel who follow best practice guidelines such as those developed by the North American Produce Transportation Working Group and those of their own companies can make an important difference. Errors made during loading can result in out-of-range temperature exposure, physical injury to product, or cross-contamination, resulting in squandered industry resources and efforts.
Before loading begins, the loader inspects and records the trailer condition. Trailer damage such as holes in the floor or loose sidewall panels can pose a safety risk. Other problems can lead to potential temperature control issues or risk of cross-contamination. For example, is the trailer pre-cooled (or pre-warmed) and the refrigeration unit functioning normally? Refrigeration chutes and ducts must not be blocked or damaged.
Ensure that trailer is clean, odor-free, and that walls are free of cracks or holes. Door seals must be in good repair and seal tightly when the doors are closed. Look for floor grooves to be clear, with load locks available to secure the load when it is completed. If the trailer does not meet GHP guidelines, contact the transportation provider to arrange for a replacement trailer.
The loader or quality assurance personnel are tasked with ensuring that product being loaded is cooled to the correct temperature. Refrigerated trailers can hold produce at the required temperature, but are not designed to remove residual field heat, if still present. When required, allow the driver to take pulp temperatures and case counts. Open topped containers such as RPCs allow easy access to product for pulping and visual inspection.
Palletized loads (also known as unit loads) should be stable and secure. Where corrugate cartons are used, it is important to build loads so that the packaging, rather than product, supports the weight from above in order to minimize compression damage to the merchandise. Most corrugated container strength is in the corners, so column stacking is the preferred approach. Attention to fully fitting the pallet footprint is an important consideration. Even a 25mm or one-inch overhang of a corrugated container beyond the edge of the pallet results in a loss of container strength of 14 to 34%. Palletized product that underhangs or does not fill the complete pallet footprint is also problematic, being more prone to shifting in transit.
Other voids within trailers should also be minimized to prevent opportunities for load shifting. For example, where weight permits, loading unit loads on the 48-inch face helps to optimize trailer cube utilization while eliminating problematic empty spaces.
Another consideration is that corrugated containers can lose up to 65% of their strength in just 10 days. While this will probably not be a factor during loading at the grower-shipper, bulging cases are a more common sight at distribution centers when store orders are being loaded. They may require a significant amount of stretch wrap to keep them stabilized during delivery to retail stores.
RPCs, on the other hand, are designed to be interlocked, while fully covering the pallet footprint. They provide a very sturdy unit load which requires only minimal stretch wrap or corner boards to enhance stability in transport, depending upon the instruction of the receiver. The use of RPCs has been found to reduce packaging damage in the fresh produce supply chain as much as 98%. After switching to RPCs, loaders and receivers can be pleasantly surprised how easily unit loads are handled. They facilitate the quick loading of vehicles, so that the doors can be closed and the refrigeration unit activated, minimizing the introduction of external heat.
Temperature recording devices should be located in the trailer in accordance with the receiver’s instructions, and tagged to allow easy identification by the consignee.
There are, of course, many nuances when it comes to loading specific commodities. This discussion serves only as a general introduction. It provides at least a brief insight into the importance of trained staff, collaborative best practices and attention to load building, all in the effort of delivering the freshest product to customers.