New antimicrobial edible coatings can extend the shelf-life of fresh meat by up to 50%

According to research from Spain, new antimicrobial edible coatings can extend the shelf-life of fresh meat by up to 50% . The films, made from essential oils including oregano, clove and rosemary, were applied to the surface of the meat “as a second skin” and were undetectable by consumers, said researcher Idoya Fernández Pan, of the Public University of Navarre. The research focused on chicken meat. “These are highly perishable foodstuffs, given their richness in nutrients and high surface moisture, which give rise to rapid colonisation and growth of a wide range of micro-organisms which are potentially highly altering, even pathogenic,” she said.
The coatings are made up of a series of antimicrobial agents that were incorporated into the structural matrix of the product, and then gradually secreted onto the surface of the meat. A bacteriostatic effect impedes the proliferation of bacteria, reduces the speed of growth of the pathogen and/or altering agent, thus enhancing the food safety of the product and extending its shelf life.
The antimicrobial properties of essential oils are well established. The Spanish researcher chose 8 different essential oils: oregano, clove, rosemary, white thyme, tea tree, coriander, sage and laurel. Edible films and coatings containing different concentrations of these oils were developed and these were shown to be effective against various microbial strains such as Staphylococcus aureus, Salmonella enteritidis, Listeria innocua and Pseudomona fragi. Oregano essential oil was found to have the greatest in vitro antimicrobial efficacy against food pathogens such as S. enteritidis and S. aureus, against altering bacteria such as P. fragi and against mixed populations. Significantly, the application of the oregano-based coating boosted shelf life by almost 50% to around 13 days in the case of chicken breast which was stored in a refrigerator.