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 environment. However, their high transparency to ultraviolet (UV) radiation limits their current commercialization. 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. Coatings 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 characterizations performed by light transmission measurements. Our results show that it is possible to enhance the UV protection of packaging using a suitable deposition with these biocompatible materials.

Sustainable biodegradable coatings for food packaging: challenges and opportunities

“…Surface modification of PLA and cellulose substrates by coating with p-coumaric acid and quinine improved their UV shielding property. 210 Similarly, the coating of carbon-dot-based solution on PLA and cellulose substrate greatly increased the UV barrier for usage in food packaging applications. 211 Overall, surface modification of paper, plastic or films as well as foodstuff through coating technology or modification of coating formulation and subsequent application on the surface could effectively improve the surface functionality in terms of resistance against environmental factors such as O 2 , H 2 O, CO 2 , UV, oil and grease.…”

“…Surface modification of PLA and cellulose substrates by coating with p -coumaric acid and quinine improved their UV shielding property. 210 Similarly, the coating of carbon-dot-based solution on PLA and cellulose substrate greatly increased the UV barrier for usage in food packaging applications. 211…”

The Characteristic Of Biocomposite Film Of Spirulina Residue As Natural Dyes

“…A comparison was conducted from the same natural dyes -carmine, turmeric, indigo and annatto-with and without encapsulation. Injected into the same PVC matrix (19), the possibility of reducing the UV transparency of two commercial and very common food packages after smart coating with commercial and green materials such as P-Coumatic acid and quinine for PLA matrix (20). Dyeing polyethylene (PE) plastic waste with bioactive photoacid phycocyanobilin (PCB) extracted from the pigment of spirulina blue-green algae the populations of long living photoproduct X*, which are pertinent to deprotonated phyrole species (anionic species) (21).…”

Synthesis and application of novel benzophenone photoinitiators

“…These intermediates initiate the crosslinking of the functional groups of the oligomers (resins) or reactive diluents (monomers) via radical polymerization curing. Compared with traditional thermal curing, UV curing offers several advantages, including short curing time, high curing efficiency, ecofriendly, [1][2][3][4][5] and widely applicated in coatings, [6][7][8][9][10] food packaging, [11][12][13][14] medicine, [9,15,16] 3D printing [17][18][19][20][21] and so on. The photoinitiator, generally comprised of 3%-5% in the photocuring formula, plays a vital role in determining photocuring speed and quality, as well as affecting surface smoothness, adhesion and the hardness of cured film.…”