title: Biodegradable Zein-Based Blend Films: Structural, Mechanical and Barrier Properties.
abstract: The effect of adding a hydrocolloid on the structural, mechanical and barrier properties of zein-based blend films is evaluated. Zein-oleic acid blend film with added xanthan gum (Z-OA-XG) showed higher water solubility (13.09%) and opacity (8.49 AU/mm) than zein-oleic acid (Z-OA) film (10.80% and 5.19 AU/mm, respectively). Furthermore, Z-OA film had greater flexibility with lower Young's Modulus (YM=5.02 MPa) and higher elongation at break (η=10.62%); nonetheless, it was less resistant to tension (tensile strengthσ=8.5 MPa) than Z-OA-XG film, which showed YM,ηandσof 6.38 MPa, 6.66% and 10.485 MPa, respectively. Both films had glossy and homogeneous structure with comparable water vapour and oxygen barrier properties around 4.39·10-11and 1.82·10-13g/(Pa·s·m), respectively. Based on that, xanthan gum structure influenced mainly mechanical and light barrier properties of zein-oleic acid blend films.
authors.affiliation: Food Engineering and Technology Department, Săo Paulo State University, Săo José do Rio Preto, Brazil; Research Group on Agrarian Sciences-GRICA, Faculty of Agrarian Sciences, University of Antioquia, Medellin, Colombia.
authors.forename: Carolina Pena
authors.initials: CP
authors.lastname: Serna
authors.affiliation: Food Engineering and Technology Department, Săo Paulo State University, Săo José do Rio Preto, Brazil.
authors.forename: José Francisco Lopes
authors.initials: JF
authors.lastname: Filho
keywords: biodegradable material; blend film; microstructure; permeability; tensile properties