Researchers use phage to create new packaging to control microbial growth

Hamilton, ON – The recent Listeria and E. coli O157:H7 outbreaks associated with cantalope and raw beef in North America reveals that the current available methods and procedures for food safety are lacking to achieve full control of these deadly pathogens. New packaging approaches, by Canadian researchers from theSentinel Bioactive Paper Network, for improving food safety offer new solutions for biocontrol by using immobilized phage.

To prevent these food-borne tragedies from happening in the future, researchers Hany Anany and Mansel Griffiths (University of Guelph) are using harmless viruses called phage to kill targeted pathogens (including Listeria and E. coli) that could be present on the surface of foods. A phage, in simple terms, is a harmless virus that can kill bacteria. An immobilized phage can take over the Listeria and/or E. coli O157:H7 bacterial cell and produce new copies of itself inside the cell. After the phage reaches critical levels, the phage breaks open the bacterial cell and destroys it, thus not allowing the pathogen to multiply on a food surface.

Sentinel researchers published work in the journal Applied and Environmental Microbiology describes their method to stick phage onto cellulose material and explains when foods (ready to eat meats, raw meats) are wrapped in the package the harmful cells of Listeria and E. coli are killed by phage that have been placed on the packaging. This packaging option works at refrigeration temperatures, at which pathogens can still grow. The packaging solution can be used for modified atmosphere and vacuum packaged meats. This is one of several technologies being investigated by the Sentinel Network, a NSERC strategic network that can help to make food-borne illness a thing of the past.

“This work has the potential to change the way today’s food packaging operates, said Dr Mansel Griffiths, a Sentinel researcher and director, Canadian Research Institute for Food Safety at the University of Guelph. “Through our research we also examined phage storage stability to further extend the use within industrial applications.”

Paper-based biosensors (bioactive paper) offer one of the best approaches for food safety monitoring because of their low-cost, simplicity, and rapid response time.

“Sentinel is working hard with its industry partners to bring phage-based anti-listeria and E. coli materials to the marketplace. One vision is food packaging that inhibits Listeria and E. coli growth and warns the consumer or food supplier of contamination,” said Dr Robert Pelton, who is Sentinel’s scientific director, McMaster University professor, and a Canada Research Chair.