ARLINGTON, Va. -- For retailers, the most pertinent concern about bacteria on fresh-cut produce may be its crucial role in causing spoilage and reducing shelf life, according to research on bacteria specific to fresh-cut produce released by the International Fresh-Cut Produce Association here.
Although 99% of bacteria can be reduced by washing, the presence of the remaining bacteria could have a detrimental effect on the product's longevity, according to a white paper from the association.
The research document was primarily intended to help educate fresh-cut produce processors on the topic of microbial problems with their products. However, the research involved in producing the white paper also showed that controlling the presence and growth of bacteria on fresh-cut produce at the store level offers retailers their principal opportunity to directly increase the shelf life of the products, according to Edith Garrett, the president of the IFPA.
As an added assurance, "retailers should make sure that their processors have Hazard Analysis Critical Control Point plans for produce and sanitary conditions. If they are cutting the produce themselves they should take the same precautions," Garrett said.
"We believe that by using HACCP and monitoring raw materials pathogenic contamination [of produce] is controlled," Garrett said.
The IFPA executive recommended several ways for retailers to further combat the spoilage caused by bacteria. Of prime importance, she said, is that fresh-cut produce should be refrigerated at cold temperatures, between 33 and 41 degrees Fahrenheit.
"That is the retailers' main responsibility, [since] they don't have it very long," she said. "They can also monitor its use by code dates and clean the shelves using the first-in, first-out system."
According to Garrett, sales of fresh-cut produce -- defined by the IFPA as produce that has been cut or altered without heat treatments -- grew to more than a billion dollars in 1996, from $100 million in 1989. But relatively little is known in the industry about the effects of bacteria on the product's performance and quality.
"There has been research published in professional journals on fresh-cut produce, but nothing for laymen," she lamented. "And fresh-cut produce has a unique microbiology that makes it different from other foods.
"From a retail standpoint, [the white paper] gives any buyer or the quality assurance department info they can use in establishing purchasing standards," Garrett said.
IFPA's white paper maintains that most of the microorganisms found on produce are harmless to humans.
"We are not producing a sterile product. When you test it, you are going to find bacteria," explained Garrett. "We are not actively trying to kill or sterilize bacteria on produce and believe that normal bacteria will outcompete pathogens," she said.
Still, there are things the industry can do to control contamination. Although, according to the white paper, fresh-cut fruits and vegetables have been linked to very few outbreaks of foodborne illness, processors should avoid using produce that they believe may have been exposed to fecal matter.
Garrett said the association recommends that retailers find ways to assure their produce sources are taking the right steps to fight contamination.
They should make sure, for example, that they are "buying from reputable processors, visiting their facilities, asking how they are buying their materials and seeing if there is a program in place to monitor them," Garrett said.
With regard to their own operations, retailers can effectively combat the growth of microorganisms presented by the large amounts of cut surfaces in a package of cut produce, combined with high humidity levels, by keeping the temperature in the case cold and not letting the product go out of date, advised Garrett.
The white paper evaluated the effectiveness of various methods used to determine bacteria levels in produce. It noted that the three top methods -- total plate count, total coliforms and fecal coliforms -- tend to provide too broad, and therefore often imprecise, a picture of bacteria levels.
Instead, the IFPA's paper recommended the use of E. coli testing as the only truly accurate indicator of the bacteria count of fresh-cut produce. E. coli counts, it said, are the most effective way to measure bacteria.
"We encourage the use of E. coli testing on produce. If you want to test for safety, test for E. coli. By itself it's not a pathogen, but the presence of that organism can be used as an indicator," added Garrett.
She added that it is the processor's responsibility, not the retailer's, to undertake such testing. "There is no reason for retailers to monitor the store. That's designed for a lab."
She went on to explain that the IFPA, since its inception, has regularly shared such recommendations with its processors.
