Fall 2009 » Research Briefs » Protein Film Protects Against Food Pathogens

Protein Film Protects Against Food Pathogens

March, 2009

An edible protein film made from soybeans can help protect refrigerated and pre-cooked, ready-to-eat food from dangerous bacteria.


From left, research specialist Earsie deFeliz, food scientist Navam Hettiarachchy and master's degree candidate Chun Kai Yang work with a machine that produces an edible protein film. Hettiarachchy's research has shown that soy protein films can be impregnated with an antimicrobial agent to provide an effective barrier against Listeria monocytogenes, a pathogen that can cause food-borne illness.
Food scientist Navam Hettiarachchy has produced edible films from soybean proteins that can be coated right on food products or used in place of plastic wrap for prepackaged foods. These films can be impregnated with antimicrobial agents that inhibit growth of bacteria such as Listeria monocytogenes.

"Soy protein films have the potential to meet a demand for biodegradable packing material, and these films can function as carriers of antimicrobials that help protect against food-borne illnesses," Hettiarachchy said. "We're trying to learn the properties of protein films that will work best as carriers for release of antimicrobials."

Two of the most important of these characteristics, she said, are their ability to either dissolve or resist dissolving when in contact with water.

The films are applied to foods by wrapping them in a dry film or by spraying them with a liquid that dries into a protective coating. Because they are edible and have no effect on flavor, they can be prepared and eaten with the food, leaving nothing to remove and throw away.

"Our tests have shown that these edible films can act as suitable carriers for delivering effective antimicrobials to the surfaces of food products," Hettiarachchy said. "They have promising applications for pharmaceuticals, fruits, vegetables and meat products."