September 28, 2016
New scientific research indicates that corrugated packaging keeps fruit fresher and safer than reusable plastic crates (RPCs) and can significantly reduce contamination from transferred microorganisms.
The research, conducted by the University of Bologna and initiated by the European Federation of Corrugated Board Manufacturers (FEFCO), found that corrugated trays ensured higher-quality packed fruits with reduced microbial cross-contamination and longer shelf life. Lower bacterial contamination decreases the risk of foodborne illnesses and increases the fruit’s freshness, scent, appearance, and taste. In both cases, the role of packaging can be critical.
Corrugated Proven Safer
Microbiological contamination of fresh produce is a very big deal for retailers and for the growers and shippers who supply them. Their entire operations and distribution chains are scrutinized whenever an outbreak is traced back to contaminated produce, and the stakes could not be higher. Pathogenic bacteria can make people very sick and sometimes even result in death.
Grower/shippers carefully consider every element in their product cycle—from growing operations to packaging and distribution—to identify potential contamination sources. When they purchase transport packaging, they need to know they are using the safest option.
We know corrugated is clean when it reaches the grower/shipper. Now, this new research shows corrugated, in addition to cushioning and protecting produce, also mitigates the spread of contamination. These findings come in the wake of other concerns being raised over the hygiene of RPCs. Last November, the Department of Food Science at the University of Arkansas showed that typical industry cleaning procedures failed to adequately sanitize RPCs. The research team, led by Dr. Steven Ricke, found salmonella cells on the crates even after cleaning. He noted that bacteria hide in the cracks and crevices of the crates’ surfaces, making it difficult for industrial sanitizers to reach them.
We know corrugated is clean when it
reaches the grower/shipper. Now, this
new research shows corrugated, in
addition to cushioning and protecting
produce, also mitigates the spread
of contamination.
Corrugated Keeps Produce Fresher
In addition to public health concerns, spoilage bacteria reduce shelf life. Freshness and appearance of a store’s produce are critical to sales. Entire supermarket chains’ success depends on the sales and profits generated in this most important retail aisle. Fresh produce is a main driver for consumers in deciding where to shop. A hefty 75 percent of shoppers say that the quality of produce is the most important factor in choosing a grocery store.1 The ability of corrugated packaging to increase shelf life could translate into significantly reduced shrink and potentially millions of dollars in savings for retailers.
Research Design
The research was led by Professor Rosalba Lanciotti at the University of Bologna’s Department of Agricultural and Food Sciences. It examined the exchange of microbes between produce and packaging and vice-versa, focused especially on determining how differences in packaging materials can influence cross-contamination.
Scientists deliberately contaminated both corrugated trays and RPCs with the same number of Escherichia coli, Saccharomyces cerevisiae, and Pseudomonas spp. microorganisms. Fresh peaches were washed with tap water, sterilized with a sodium solution, rinsed with sterilized water, and then air-dried before being placed into the containers for testing. Next, researchers measured the levels of bacteria that transferred to the fruit over time.
Results
The results showed that fruit packed in corrugated fared better—with fewer transferred pathogenic and spoilage bacteria—than the fruit packed in RPCs. The differences in microbiological quality were statistically significant.
Fruit packed in plastic crates reached contamination levels generally associated with spoilage 48 to 72 hours earlier than the fruit packed in corrugated trays.
Contributing factors such as storage temperature, length of time before sale, and superficial damage on the peaches were also considered. Results showed that all these factors influenced the microbial transfer from packaging material to fruit, but the transfer of spoilage microorganisms was always lower in corrugated trays.
The tests also showed that in some conditions (e.g., high storage temperature), up to 95 percent of peaches packed in the deliberately contaminated RPCs were infected with E. coli after 48 hours. By contrast, the E. coli contamination level never exceeded 25 percent of the peaches packed in corrugated containers that had been contaminated with the same levels of microorganisms.
The Big Picture
Corrugated has long been the shipping container of choice for most grocery products. The RPC industry is targeting fresh produce for conversion away from corrugated. Our industry has long-term, established relationships with growers and shippers who predominantly prefer to keep using corrugated for many time-honored reasons. As an industry, we are responsible for obtaining and sharing verified, third-party-generated facts that support grower/shippers’ preference for corrugated. This latest research is one in a long line of scientific studies that proves, once again, that corrugated makes the most sense.
Dennis Colley is the executive director of the Corrugated Packaging Alliance and president of the Fibre Box Association. He can be reached at 847-364-9600 or dcolley@fibrebox.org.
