title: Formation of type 4 resistant starch and maltodextrins from amylose and amylopectin upon dry heating: A model study.
abstract: Starch is one of the main components of human diet. During food processing, starch is submitted to high temperatures in the presence or absence of water. Thus, the main goal of this work was to identify structural modifications caused by dry heating in starch polysaccharides (amylose and amylopectin) and structurally related oligosaccharides, maltotetraose (M4) and glucosyl-maltotriose (GM3), simulating processing conditions. The structural modifications were evaluated by methylation analysis, electrospray mass spectrometry (ESI-MS), tandem mass spectrometry (ESI-MS/MS) and anionic chromatography after in vitro enzymatic digestion. Dry heating promoted dehydration, depolymerization, as well as changes in Glc glycosidic linkage positions and anomeric configuration. In oligosaccharides, polymerization was also observed. All these changes resulted in a lower in vitro digestibility, suggesting that dry heating of starch polysaccharides and related oligosaccharides may be associated with the formation of type 4 resistant starch and maltodextrins, non-digestible carbohydrates that are responsible for beneficial effects in human intestinal tract.
authors.affiliation: CQ-VR, Chemistry Research Centre, Department of Chemistry, University of Trás-os-Montes e Alto Douro, 5001-801 Vila Real, Portugal.
authors.forename: Fernando M
authors.initials: FM
authors.lastname: Nunes
authors.affiliation: QOPNA, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal.
authors.forename: Edgar S
authors.initials: ES
authors.lastname: Lopes
authors.affiliation: QOPNA, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal.
authors.forename: Ana S P
authors.initials: AS
authors.lastname: Moreira
authors.affiliation: QOPNA, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal.
authors.forename: Joana
authors.initials: J
authors.lastname: Simões
authors.affiliation: QOPNA, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal.
authors.forename: Manuel A
authors.initials: MA
authors.lastname: Coimbra
authors.affiliation: QOPNA, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal. Electronic address: mrd@ua.pt.
authors.forename: Rosário M
authors.initials: RM
authors.lastname: Domingues
mesh_terms: D000687:Amylopectin / Q000737:chemistry*; D000688:Amylose / Q000737:chemistry*; D006358:Hot Temperature; D006868:Hydrolysis; D058105:Polymerization; D011134:Polysaccharides / Q000737:chemistry*
chemical_list: D011134:Polysaccharides; C008315:maltodextrin; D000688:Amylose; D000687:Amylopectin
keywords: Anomeric configuration; Oligosaccharides; Polymerization; Polysaccharides; Roast; Type 4 resistant starch