Bacteria can take a ride and proliferate on the plastic wrap that foods are commonly packaged in. Researchers at Penn State have developed a way to bond a non-toxic transparent antimicrobial material to the ubiquitous polyethylene wrap that meats, vegetables, and mushrooms are sold in. The antimicrobial layer is made of a pullulan-based biopolymer, itself derived from starch syrup and approved by FDA for use with foods. It is a chain of glycerin, sugar, and cellulose molecules, but to make it kill bacteria it was infused with lauric arginate, also an approved product that comes from natural sources and which shows wide spectrum antimicrobial effects. The pullulan works to hold onto the lauric arginate while slowly releasing it, providing a long term effect. This was a challenge because the pullulan had to be specially modified for the task and the hydrophobicity of the polyethylene plastic had to also be overcome. To evaluate the effectiveness of the new film, the team wrapped meats inoculated with four common food related pathogens and let them stay in a fridge for almost a month. The material showed impressive ability to keep bacteria away from its surface, helping to preserve the meats within longer than with traditional plastic wrap. Study in International Journal of Food Microbiology: Development and evaluation of pullulan-based composite antimicrobial films (CAF) incorporated with nisin, thymol and lauric arginate to reduce foodborne pathogens associated with muscle foods Raw beef inoculated with pathogens then vacuum packaged with the composite antimicrobial film, sealed and placed into refrigerated storage. The composite antimicrobial film significantly reduced foodborne pathogens on the experimentally inoculated surfaces of the raw and ready-to-eat muscle foods. Source
