We began the last article saying this: no one would board an airplane if the pilot could only find out the plane was low on fuel fifteen minutes before the tank was empty. Yet fresh produce is typically monitored only by visual inspection, putting the retailer in a similar situation. Fortunately, fresh produce shippers and retailers can now receive a real-time picture of how much shelf life is "in the tank" by using automated data capture technology, beginning at harvest.

Early and effective pre-cooling is the single most important factor for preserving produce shelf life and reducing invisible shrink. Last week's article cited University of Florida research documenting huge losses in California strawberries shipped to the Southeast when pre-cooling was delayed by four or more hours. In that study, produce inspection at the retailer DC was unable to determine differences between properly and improperly pre-cooled strawberries.

Special pre-cooling systems force air through pallets, with packaging designed to maximize airflow. Proper pre-cooling makes product in the center of a pallet cool enough for optimum shelf life; but the temperature in the center of pallets is not typically measured.

We have found that incomplete and variable pre-cooling, the process using specialized equipment to get field heat out of a pallet very rapidly, caused 30% to 40% of the produce quality issues experienced along the supply chain. Pre-cooling must be done both promptly and properly to maintain optimum produce temperature.

A Graphical Picture of Proper Pre-Cooling

Produce temperature during transportation is usually measured by truck ambient air temperatures, resulting in data logs like the ambient air temperature charts for a truckload of blackberries below. Using temperature monitors located inside one of the cases on each of the pallets, we measured what the temperature actually was "inside the case." Variations between truck and product temperatures may be seen by comparing the truck temperatures with the bottom line of graphs, where colored lines chart the actual product temperature for each pallet.

Just a glance at these tiny charts reveals great variability between pallet and truck temperatures. What is happening "inside the case" can vary greatly on the same truckload. Temperature monitoring determines those differences, helping manage the product in line with its actual shelf life.

Achieving Effective and Consistent Pre-Cooling

New automated solutions are available to measure the air going into and coming out of each pallet, giving 'at a glance' information about how much field heat remains in each pallet. Using these new solutions can save time and energy, reducing pre-cooler time for some pallets and identifying other pallets needing additional pre-cooling. This can eliminate the 30% to 40% of 'hot pallets in transit' illustrated in the above charts.

The Takeaway: Proper Pre-Cooling and Inventory Management by First Expiring First Out, not FIFO

Properly pre-cooled product, coupled with time and temperature data, allows both shipper and retailer to match product shelf life to a proper location. For the blackberries we tracked, reduced warehouse and transit time put 99% of blackberries in a location appropriate for their shelf life, rather than 43%.

We reduced risk of invisible shrink loss from 57% to 1% when we used automated real-time temperature monitoring data to calculate accelerated shelf life loss, optimizing inventory rotation and routing. New technology exists to seamlessly provide this pallet-level data by recording produce temperature "inside the case."

These new solutions can provide operations real-time, actionable temperature information that can significantly improve pre-cooling, inventory rotation and routing decisions. The new technology may be integrated into existing systems, improving product quality and freshness, increasing profitability, and increasing product demand from both retailers and consumers. These new solutions are a great improvement over current pre-cooling procedures and last-minute shelf life "alarms" given by systems lacking precise temperature data history.

Mike Nicometo is President of EmpowerTech, Inc., providing expertise in logistics processes, cool supply chain management, project management, roadmap development & control, global team leadership, software prototyping and business development. Contact him at 906-774-5532 or mike@nicometo.com.