title: Chitosan-caseinate bilayer coatings for paper packaging materials.
abstract: Papers coated with caseinate and caseinate/chitosan bilayer films were developed. Caseinate, chitosan and caseinate/chitosan films were preliminary characterized by FTIR spectroscopy and thermal stability analyses. The effects of coating weight, caseinate concentration (7%, 10%, and 12%, w/w), and coating application methods (single layer and bilayer) on the physical and mechanical properties of coated papers were studied. Increasing the concentration of caseinate led to a decrease in water vapor permeability (WVP) of the resulting coated paper sheets. Chitosan significantly (p<0.05) increased the elongation at break (%E) of coated paper. However, the application of chitosan as a second layer on wet or dry caseinate films did not significantly affect (p>0.05) the tensile strength (TS) of coated paper. The greatest reduction in paper WVP is achieved by addition of a chitosan layer to the dried preformed caseinate-coated paper.
authors.affiliation: Laboratoire des Substances Naturelles (LSN), Institut National de Recherche et d'Analyse Physico-chimique (INRAP), Pôle Technologique de Sidi Thabet, 2020 Sidi Thabet, Tunisia. Electronic address: khaoula_khwaldia@yahoo.fr.
authors.forename: Khaoula
authors.initials: K
authors.lastname: Khwaldia
authors.forename: Altaf H
authors.initials: AH
authors.lastname: Basta
authors.forename: Hajer
authors.initials: H
authors.lastname: Aloui
authors.forename: Houssni
authors.initials: H
authors.lastname: El-Saied
mesh_terms: D002364:Caseins / Q000737:chemistry*; D048271:Chitosan / Q000737:chemistry*; D018857:Food Packaging; D006801:Humans; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D010209:Paper; D010539:Permeability; D017550:Spectroscopy, Fourier Transform Infrared; D013227:Steam / Q000032:analysis; D013718:Tensile Strength
chemical_list: D002364:Caseins; D013227:Steam; D048271:Chitosan
keywords: Bilayer coating; Caseinate; Chitosan; Composite coating; Functional properties; Paper