Researchers at Penn State University’s College of Agricultural Sciences have purportedly found that edible films made from pullulan—a transparent polymer produced by the fungus Aureobasidium pulluns, silver nanoparticles, zinc oxide, and oregano and rosemary essential oils—can inhibit foodborne pathogens on meat products. Mohamed K. Morsy, et al., “Incorporation of Essential Oils and Nanoparticles in Pullulan Films to Control Foodborne Pathogens on Meat and Poultry Products,” Journal of Food Science, April 2014.

Observing that the films inhibited the growth of four pathogens—Staphylococcus aureus, Salmonella Typhimurium, Listeria monocytogenes, and E. coli O157:H7—to varying degrees, the researchers concluded that they could form “the basis of a useful packaging tool to improve the safety of meat products.” According to Penn State University Food Science Professor Catherine Cutter, who co-authored the study, the edible films are a “novel but effective way” to deliver antimicrobial agents to meats because the bacteria-killing action lasts longer than the liquid applications traditionally used.

“The results from this study demonstrated that edible films made from pullulan and incorporated with essential oils or nanoparticles have the potential to improve the safety of refrigerated, fresh or further-processed meat and poultry products,” said Cutter. “The research shows that we can apply these food-grade films and have them do double duty—releasing antimicrobials and imparting characteristics to protect and improve food we eat.” See Penn