USDA researchers have long known that carvacrol, an extract from oregano, is a powerful antimicrobial that kills foodborne pathogens including E. coli 0157:H7, Salmonella and Listeria. Now they have figured out a way to make “edible films” infused with carvacrol that they say could be inserted into packaged fresh produce to prevent the development of pathogens.
The edible films are five-thousands of an inch thick, and can be made of pureed vegetables or fruits. Carvacrol, the predominant essential oil in oregano, would add a pleasant—and protective—accent to a spinach-purée film that could be placed inside a bag of spinach, for example. Already shown in lab investigations to be an effective weapon against several major foodborne pathogens, carvacrol currently flavors some popular salad dressings and seasoning mixes. Carvacrol vapors wafting from the wedge into the atmosphere inside the sealed bag would both season and safen the spinach.
USDA scientists estimate that antimicrobial film inserts for packaged leafy greens—a spinach-purée wedge, a colorful square of carrot-based film, or other innovative options—might be ready within a year or so to test and evaluate at fresh-produce packinghouses. (http://www.ars.usda.gov/is/AR/archive/jul08/salads0708.htm)