title: Agro-industrial residue from starch extraction of Pachyrhizus ahipa as filler of thermoplastic corn starch films.
abstract: Biocomposites films based on thermoplastic corn starch (TPS) containing 0.5% w/w fibrous residue from Pachyrhizus ahipa starch extraction (PASR) were obtained by melt-mixing and compression molding. PASR is mainly constituted by remaining cell walls and natural fibers, revealed by Scanning Electron Microscopy (SEM). Chemical composition of the residue indicated that fiber and starch were the principal components. Biocomposites thermo-stability was determined by Thermo-Gravimetric Analysis. A continuous PASR-TPS interface was observed by SEM, as a result of a good adhesion of the fibrous residue to starch matrix. Likewise, films containing PASR presented fewer superficial cracks than TPS ones, whereas their fracture surfaces were more irregular. Besides, the presence of PASR increased starch films roughness, due to fibers agglomerates. Films reinforced with PASR showed significantly lower water vapor permeability (WVP). In addition, PARS filler increased maximum tensile strength and Young's modulus of TPS films, thus leading to more resistant starch matrixes.
authors.affiliation: Planta Piloto de Ingeniería Química, PLAPIQUI (UNS-CONICET), Departamento de Ingeniería Química, UNS, Camino La Carrindanga km 7, 8000 Bahía Blanca, Argentina.
authors.forename: O V
authors.initials: OV
authors.lastname: López
authors.affiliation: Centro de Investigación y Desarrollo en Criotecnología de Alimentos, CIDCA (UNLP-CONICET), Facultad de Ciencias Exactas, UNLP, 47 y 116, 1900 La Plata, Argentina.
authors.forename: F
authors.initials: F
authors.lastname: Versino
authors.affiliation: Planta Piloto de Ingeniería Química, PLAPIQUI (UNS-CONICET), Departamento de Ingeniería Química, UNS, Camino La Carrindanga km 7, 8000 Bahía Blanca, Argentina.
authors.forename: M A
authors.initials: MA
authors.lastname: Villar
authors.affiliation: Centro de Investigación y Desarrollo en Criotecnología de Alimentos, CIDCA (UNLP-CONICET), Facultad de Ciencias Exactas, UNLP, 47 y 116, 1900 La Plata, Argentina. Electronic address: magarcia@quimica.unlp.edu.ar.
authors.forename: M A
authors.initials: MA
authors.lastname: García
mesh_terms: D029905:Pachyrhizus / Q000737:chemistry*; D010539:Permeability; D013213:Starch / Q000737:chemistry* / Q000648:ultrastructure; D013227:Steam / Q000032:analysis; D013718:Tensile Strength; D013818:Thermogravimetry; D003313:Zea mays / Q000737:chemistry*
chemical_list: D013227:Steam; D013213:Starch
keywords: Barrier and mechanical properties; Biocomposite films; Fibrous residue; Structure characterization; Thermoplastic starch