Recent food safety scares have heightened consumer awareness and created a push for more research into the cause and prevention of foodborne illness outbreaks.


Three Virginia Tech researchers have begun projects in that direction.


Monica Ponder, assistant professor of food science and technology, is examining the molecular interactions among microbial populations on spinach.


Some naturally occurring bacteria may compete with the illness-causing organisms.


Already, she's identified 35 bacteria species on spinach that inhibit the growth of E. coli and Salmonella under laboratory conditions.


“The ability to identify and quantify the antimicrobial effects of these bacteria on the safety of the spinach plant holds the promise of natural controls over food-borne pathogens in fresh spinach,” Ponder said in a news release.


In addition, she and horticulture prfessor Greg Welbaum are examining whether spinach seeds may carry food pathogens and move them into the plant leaves as they grow.


Renee Boyer, assistant professor of food science and technology and Extension food safety specialist, is studying the effect that modified-atmosphere packaging has on the survival of E. coli O157: H7 on lettuce and spinach.


This is the same technology used for bagged leafy greens in the grocery store.


“The study shows that the modified atmosphere packaging will not control or reduce populations of E. coli once they are present,” Boyer saidin the release. “This stresses the importance of preventing contamination at the farm and packinghouse level.”


Boyer is also collaborating with colleague Robert Williams to determine the effect of high-pressure processing on whole and diced red tomatoes contaminated with Salmonella.


This initiative, funded in part by the Virginia Agriculture Council, involves inoculating store-bought tomatoes with Salmonella, exposing the tomatoes to three different pressures, and examining the microbial counts and quality of the tomatoes after treatment.


The researchers also are interested in the effects high pressure will have on green, unripened tomatoes, and whether the pressure treatment will inactivate the enzymes involved in ripening.