Study: Reusable Plastic Produce Containers Harbor Bacteria Even After Being Cleaned, Sanitized

Bacterial biofilms could survive on the surface of RPC material.

Reusable plastic containers used to transport large amounts of fruits and vegetables to grocery stores can continue to harbor potentially harmful bacteria directly on their surfaces, even after undergoing industry-standard cleaning and sanitizing, according to a new study conducted by researchers from the University of Arkansas and WBA Analytical Laboratories.

http://www.dreamstime.com/stock-photography-colorful-boxes-plastic-crates-containers-fish-packing-piles-storage-catch-image33735962.The study took a microscopically close look at the materials used to make the reusable plastic containers (RPCs) that have gained a foothold in the grocery industry in recent years as a preferred method of transporting produce.

The findings suggest that a return to single-use containers for fresh produce might reduce the risk of foodborne illness outbreaks associated with those products. The researchers allowed Salmonella, Listeria monocytogenes and E. coli O157:H7 bacteria to grow on the RPC surface and then subjected sample surfaces to cleaning and sanitizing practices typical in the industry. In all cases, the materials still harbored biofilms that protected the bacteria and would theoretically allow bacteria to colonize the next shipment of fruits and vegetables to be put in the containers.

Anytime you start using these things over and over again, you increase the opportunities for pathogens to propagate, it is really increasing the chance of bacteria getting fixed to the surface.”

The study was to see whether or not bacterial biofilms could survive on the surface of RPC material. After cleaning, they examined RPC samples with a scanning electron microscope (SEM) and found the bacteria on every sample cleaned. It is interesting this results when the containers appear clean to the naked eye. Data suggest the rough surfaces might be easier for bacteria to colonize. Obviously the presence of bacteria after cleaning meant that the possibility of disease transmission could not be ruled out

The industry needs to look into doing a risk assessment and cost assessment of using RPCs for transporting produce, adding that he knew the suggestion makes him sound.

The plastic containers have been under scrutiny from certain food safety academics in recent years. Researchers from both the University of California-Davis and the University of Guelph have conducted studies finding that RPCs are often still contaminated when delivered to produce packers.

Source: Food Safety News