title: Development of a low glycemic maize starch: preparation and characterization.
abstract: A low glycemic index starch was developed by partial alpha-amylase treatment, and its fine structure responsible for slowly digestible and resistant properties was investigated. Different digestion rates were obtained for gelatinized, retrograded starch by varying the enzyme dosage and reaction time. Analysis by high performance size-exclusion chromatography (HPSEC) coupled with multiangle laser-light scattering indicated that the molecular weighs of amylopectin and amylose were reduced during the digestion, to less than 100 kDa. A debranched chain length study using high performance anion-exchange chromatography equipped with an amyloglucosidase reactor and a pulsed amperometric detector and HPSEC revealed that short chains of amylopectin and noncrystalline amylose were rapidly digested, while DPn 121 chains showed resistance, followed by DPn 46 chains. X-ray diffraction analysis revealed that the crystalline structure in the treated starches survived cooking. These starches not only have slowly digestible and resistant character, but also retain some branched structure for adequate functionality.
authors.affiliation: Whistler Center for Carbohydrate Research and Department of Food Science, 745 Agriculture Mall Drive, Purdue University, West Lafayette, Indiana 47907-2009, USA.
authors.forename: Xian-Zhong
authors.initials: XZ
authors.lastname: Han
authors.forename: Zihua
authors.initials: Z
authors.lastname: Ao
authors.forename: Srinivas
authors.initials: S
authors.lastname: Janaswamy
authors.forename: Jay-Lin
authors.initials: JL
authors.lastname: Jane
authors.forename: Rengaswami
authors.initials: R
authors.lastname: Chandrasekaran
authors.forename: Bruce R
authors.initials: BR
authors.lastname: Hamaker
mesh_terms: D000284:Administration, Oral; D000818:Animals; D003296:Cooking / Q000379:methods; D004038:Diet, Reducing; D002149:Energy Intake; D038321:Glycemic Index; D066298:In Vitro Techniques; D008970:Molecular Weight; D051381:Rats; D017207:Rats, Sprague-Dawley; D013213:Starch / Q000008:administration & dosage / Q000138:chemical synthesis* / Q000737:chemistry*; D013696:Temperature; D014783:Viscosity; D014961:X-Ray Diffraction; D003313:Zea mays / Q000737:chemistry*; D000516:alpha-Amylases / Q000737:chemistry
chemical_list: D013213:Starch; D000516:alpha-Amylases