title: Bio-based coatings as potential barriers to chemical contaminants from recycled paper and board for food packaging.
abstract: Partition and diffusion experiments were carried out with paper and board samples coated with different biopolymers. The aim was to evaluate the physicochemical behaviour and barrier properties of bio-coatings against migration of typical contaminants from recycled paper packaging. Focus was directed towards water-based, renewable biopolymers, such as modified starches (cationic starch and cationic waxy starch), plant and animal proteins (gluten and gelatine), poured onto paper with an automatic applicator. Additionally, a comparison with polyethylene-laminated paper was performed. Microstructural observations of the bio-coated paper allowed the characterisation of samples. From the partitioning studies, considerable differences in the adsorption behaviour of the selected contaminants between bio-coated or uncoated paper and air were highlighted. For both the polar and non-polar compounds considered (benzophenone and diisobutyl phthalate, respectively), the lowest values of partition coefficients were found when paper was bio-coated, making it evident that biopolymers acted as chemical/physical barriers towards these contaminants. These findings are discussed considering the characteristics of the tested biopolymers. Diffusion studies into the solid food simulant poly 2,6-diphenyl-p-phenylene oxide, also known as Tenax(®), confirmed that all the tested biopolymers slowed down migration. The Weibull kinetic model was fitted to the experimental data to compare migration from paper and bio-coated paper. Values found for β, an index determining the pattern of curvature, ranged from 1.1 to 1.7 for uncoated and polyethylene paper, whereas for bio-coated papers they ranged from 2.2 to 4.9, corresponding to the presence of an evident lag phase due to barrier properties of the tested bio-coatings.
authors.affiliation: a DeFens, Department of Food Environmental and Nutritional Sciences, Packaging Division , Università degli Studi di Milano , I-20133 Milan , Italy.
authors.forename: V
authors.initials: V
authors.lastname: Guazzotti
authors.forename: A
authors.initials: A
authors.lastname: Marti
authors.forename: L
authors.initials: L
authors.lastname: Piergiovanni
authors.forename: S
authors.initials: S
authors.lastname: Limbo
mesh_terms: D000327:Adsorption; D001577:Benzophenones / Q000032:analysis / Q000633:toxicity; D001704:Biopolymers / Q000737:chemistry; D020099:Coated Materials, Biocompatible / Q000737:chemistry; D003993:Dibutyl Phthalate / Q000031:analogs & derivatives / Q000032:analysis / Q000633:toxicity; D004058:Diffusion; D005506:Food Contamination / Q000517:prevention & control*; D018857:Food Packaging / Q000379:methods*; D059022:Food Safety; D005782:Gels; D006801:Humans; D008855:Microscopy, Electron, Scanning; D010209:Paper; D020959:Polyethylene / Q000737:chemistry; D059027:Recycling; D013213:Starch / Q000737:chemistry
chemical_list: D001577:Benzophenones; D001704:Biopolymers; D020099:Coated Materials, Biocompatible; D005782:Gels; D003993:Dibutyl Phthalate; C047723:benzophenone; D020959:Polyethylene; D013213:Starch; C025605:diisobutyl phthalate