Manufacturing "Sterilizes" Corrugated Boxes for Food Packaging

According to a recent article in Food Safety News, Seattle, Wash., USA, a new study confirms what proponents of single-use corrugated containers have been saying for years, that "the corrugating process uses temperatures high enough to kill germs, ensuring that the boxes don’t introduce pathogens into the food supply chain."
The article by Food Safety News writer Coral Beach quoted Maryann Sanders, senior regulatory specialist and microbiologist at Haley & Aldrich Inc., who directed the NSF International study, (sponsored by the Corrugated Packaging Alliance) as to the purpose of the study: "The main point of the study was to make sure our house is in order. We had the hypothesis but it hadn’t been proven until this research was done," Sanders said when the study results were released earlier this month.
Sanders has been working with the corrugated industry for 10 years. As a microbiologist, she knew that pathogens couldn’t survive the high temperatures of 180o to 200o F used to shape and bond layers of paper into the rigid corrugated material known to laymen as "cardboard" and corrugated containerboard to people within the industry. However, no one had specifically documented that fact.

Also, the article points out, no one has documented a food-borne illness caused by pathogens on reusable plastic containers (RPCs), which some retailers have begun requiring for fresh produce shipments. Sanders added that "If I were a retailer or a supplier, I wouldn’t want to be the first one to have a documented problem," 

Sanders additionally noted that research sponsored by the RPC industry has shown high levels of pathogens on the reusable containers. That research showed RPCs on the same pallet ranged from zero microbial organisms to 10 million organisms. Sanders said she suspects the wildly different levels are a reflection of inadequate or improper sanitizing between uses.

Trevor Suslow, an extension specialist and food safety researcher at the University of California-Davis, consulted on both the RPC study and the corrugated study. He said that fresh produce growers and shippers frequently ask him whether they should use single-use corrugated containers or RPCs. The answer is not easily determined.

Suslow said the basic concept of multi-use containers sets them up to become contaminated, especially if they are used for commodities that are packed in the field, which includes many fresh produce commodities. "If you are required to use RPCs, be sure to inspect them upon receipt," Suslow said in the Food Safety News article. "If you see a problem, document it. You can also use quick swab tests to check the general levels of (microbial growth)."

Sanders, however, emphasized that such precautions are unnecessary with single-use corrugated containers.