doi:10.1038/nindia.2018.33 Published online 15 March 2018
Researchers have synthesised biodegradable nanocomposite films that can be used as food-packaging material1. This material also inhibits the growth of specific bacteria, making it potentially useful for producing antimicrobial food wrapping.
Existing food-wrapping materials are mostly made from synthetic polymers that don’t degrade and persist in the environment, releasing toxic by-products.
To prepare eco-friendly food wrappers, scientists from the University of Calcutta, in Kolkata, India, made the nanocomposite films using a cellulose-based compound, a polymer and an organic-compound-modified clay. They then tested these films’ potential to be used as food-wrapping material.
The films contained clay layers that remained loaded into the polymer matrix in a way that it created an impermeable barrier to water vapour – an essential quality of a good food-packaging material. Experiments with ultraviolet and visible light revealed that the films were also transparent, an important feature of potential food-wrappers.
When exposed to specific bacteria growing in a nutrient broth, the films inhibited their growth, indicating their antimicrobial potential. The films were non-toxic to human blood up to the concentration of 20mg/ml – an important property that shows their biocompatibility.
These results suggest that the films could potentially be used to make packaging material to safely store food for human consumption, say the researchers.
1. Saha, N. R. et al. Development of active packaging material based on cellulose acetate butyrate/polyethylene glycol/aryl ammonium cation modified clay. Carbohydr. Polymer. 187, 8-18 (2018)