Natural Dyes Used as Organic Coatings UV Protecting for Food Packages

Abstract: Nowadays, the use of biodegradable and bio-derived plastics such as poly(lactic acid) (PLA) and cellulose in food packaging applications are replacing the use of different and more conventional oil-derived polymers that are much more expensive and unsuitable for the envi-ronment. However, their high transparency to UV radiation limits their current commer-cialization. Therefore, this study focuses on the deposition of organic thin films on commercial PLA and cellulose in order to enhance their performance, in particular for UV shielding. Coat-ings with different natural and biocompatible (edible) molecules, quinine and p-Coumaric acid, dispersed in different matrices are deposited by comparing different deposition techniques such as spray coating and spin coating. Morphological characterizations are carried out with atomic force microscopy (AFM) and scanning electron microscopy (SEM), with spectroscopic characteri-zations performed by light transmission measurements . Our results show that it is possi-ble to enhance the UV protection of packaging using a suitable deposition with these biocom-patible materials