title: Improved material properties of solution-cast starch films: Effect of varying amylopectin structure and amylose content of starch from genetically modified potatoes.
abstract: High-amylose potato starches were produced through genetic modification resulting in changed granule morphology and composition, with higher amylose content and increased chain length of amylopectin. The increased amylose content and structural changes in amylopectin enhanced film-forming behavior and improved barrier and tensile properties in starch films. The molecular structure in these starches was related to film-forming properties. Solution-cast films of high-amylose starch revealed a homogeneous structure with increasing surface roughness at higher amylose content, possibly due to amylose aggregation. Films exhibited significantly higher stress and strain at break compared with films of wild-type starch, which could be attributable to the longer chains of amylopectin being involved in the interconnected network and more interaction between chains, as shown using transmission electron microscopy. The oxygen permeability of high-amylose starch films was significantly decreased compared with wild-type starch. The nature of the modified starches makes them an interesting candidate for replacement of non-renewable oxygen and grease barrier polymers used today.
authors.affiliation: Department of Food Science, Swedish University of Agricultural Sciences, Box 7051, SE-750 07 Uppsala, Sweden. Electronic address: carolin.menzel@slu.se.
authors.forename: Carolin
authors.initials: C
authors.lastname: Menzel
authors.affiliation: Department of Plant Breeding, Swedish University of Agricultural Sciences, Box 101, SE-230 53 Alnarp, Sweden.
authors.forename: Mariette
authors.initials: M
authors.lastname: Andersson
authors.affiliation: Department of Food Science, Swedish University of Agricultural Sciences, Box 7051, SE-750 07 Uppsala, Sweden.
authors.forename: Roger
authors.initials: R
authors.lastname: Andersson
authors.affiliation: Department of Food Science, Swedish University of Agricultural Sciences, Box 7051, SE-750 07 Uppsala, Sweden.
authors.forename: José L
authors.initials: JL
authors.lastname: Vázquez-Gutiérrez
authors.affiliation: Department of Forest Products, Swedish University of Agricultural Sciences, Box 7008, SE-750 07 Uppsala, Sweden.
authors.forename: Geoffrey
authors.initials: G
authors.lastname: Daniel
authors.affiliation: Department of Food Science, Swedish University of Agricultural Sciences, Box 7051, SE-750 07 Uppsala, Sweden.
authors.forename: Maud
authors.initials: M
authors.lastname: Langton
authors.affiliation: Innventia AB, Box 5604, SE-114 86 Stockholm, Sweden.
authors.forename: Mikael
authors.initials: M
authors.lastname: Gällstedt
authors.affiliation: Department of Food Science, Swedish University of Agricultural Sciences, Box 7051, SE-750 07 Uppsala, Sweden.
authors.forename: Kristine
authors.initials: K
authors.lastname: Koch
mesh_terms: D000687:Amylopectin / Q000737:chemistry*; D000688:Amylose / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D008859:Microscopy, Polarization; D015394:Molecular Structure; D030821:Plants, Genetically Modified / Q000254:growth & development / Q000378:metabolism*; D011198:Solanum tuberosum / Q000254:growth & development / Q000378:metabolism*; D012996:Solutions; D013213:Starch / Q000737:chemistry* / Q000648:ultrastructure; D014961:X-Ray Diffraction
chemical_list: D012996:Solutions; D013213:Starch; D000688:Amylose; D000687:Amylopectin
keywords: Amylopectin; Chain-length; Film forming; High-amylose potato starch; Microscopy; Molecular structure