Inbound Logistics | December 2022

W hat’s the difference between a bowl of luscious strawberries and a bowl of moldy mush? It might come down to just a few degrees of temperature. “The opportunity to get things wrong in maintaining the cold chain is quite signicant,” says Jez Pile, director, enterprise food supply chain platforms at Telus Agriculture and Consumer Goods, based in Calgary, Alberta. On the journey from producer to consumers—involving transportation, storage, loading, and unloading— temperature-sensitive produce passes through many points where handling errors could reduce quality and safety, says Pile, whose company’s products include a temperature monitoring system for fresh food. “It’s all about minimizing the touches,” says Stu Kaminsky, owner of Agri Exotic Trading, a wholesale distributor of fresh produce in Clifton, New Jersey. “You pick up at the shipping point and then receive the product in your warehouse with close attention to the cold chain.” Refrigerated processed foods and frozen foods face similar challenges. Each product needs to stay at the optimal temperature from origin to destination. FROM PRE-COOLING TO UNLOADING The effort to preserve the cold chain starts even before a supplier loads food onto a refrigerated truck. “The role of the reefer is not to cool the product, but to maintain the temperature,” says Jake McPaul, head of refrigerated operations and product in the Fresh Freight division of WARP, a Los Angeles-based third- party logistics (3PL) company and technology developer. Pre-cooling is the supplier’s job, and this step is crucial. “When warmer product goes on a truck, that takes the shelf life right out of it,” says John Druckenmiller, general manager at Kool Logistics in Brentwood, Tennessee, which transports

temperature- sensitive foods, including fresh and frozen and some refrigerated goods. Kool Logistics drivers use “pulp thermometers” to check whether produce is sufciently cooled before loading. sufciently loading. and goods. Telus's RFID smart tags monitor temperature in transit.

Refrigerated trailers or containers keep food properly cooled in transit. One challenge arises when a load includes products with different needs. Take peppers, which should stay at about 42 degrees F. When they share a trailer with produce that’s happiest at 35 degrees, peppers need to bundle up for the ride. “We have the shipper ‘paper’ the product,” says Druckenmiller. “It creates insulation, keeping the air ow from getting the product too cold.” Technology that monitors temperature in transit also helps to maintain the cold chain. Telus Agriculture and Consumer Goods provides a thin, autonomous sensor tag that shippers attach to produce, often on the outside of cartons. The tag records the temperature of the product itself—not just the air at the rear of the trailer—every ve to 15 minutes, creating a digital log. “When product arrives at its destination, the data is automatically downloaded,” Pile says. A wireless gateway, operating on an open-source internet of things (IoT) network, captures the data when a tag comes within range. Telus’s system then checks the log to see if the temperature ever veered too far during the trip. “If there are issues, our platform automatically noties relevant stakeholders.” Pile says. The tag can also tell if product was left too long in the wrong environment during loading or unloading. And the platform can aggregate and analyze data trailers or containers

from many shipments, using articial intelligence (AI) to spot weak links in the cold chain so the shipper can correct them. While some monitoring systems provide a temperature log at the end of a trip, others trigger action in real time. “We can ping the driver and say, ‘At your next stop, document the temperature in your reefer and upload it here,’” says McPaul. “The driver will take a photo of the reefer’s temperature display and use WARP’s solution to provide it to the shipper.” Some tracking systems built into reefers transmit alerts when things go wrong. “If the product goes above 37 degrees [if that’s the top of the permissible range], we receive an alarm or an e-mail saying, ‘There’s a problem. Have the driver check the unit,’” Druckenmiller says. When a driver can’t x a malfunctioning reefer, the shipper or its 3PL might take other steps to rescue the load. “We can leverage our network of crossdocks,” says McPaul. “Hopefully there’s one close, and we can get the product off temporarily, maintain the temperature, and bring in a properly functioning unit to carry on the rest of the way.” Unloading also poses problems for the cold chain. Even when the reefer keeps blowing cold air, and even when the loading dock is cooled, hot outdoor temperatures can take a toll if the transfer from truck to building takes too long.

34 Inbound Logistics • December 2022