title: Structure of Waxy Maize Starch Hydrolyzed by Maltogenic α-Amylase in Relation to Its Retrogradation.
abstract: Maltogenic α-amylase is widely used as an antistaling agent in bakery foods. The objective of this study was to determine the degree of hydrolysis (DH) and starch structure after maltogenic amylase treatments in relation to its retrogradation. Waxy maize starch was cooked and hydrolyzed to different degrees by a maltogenic amylase. High-performance anion-exchange chromatography and size exclusion chromatography were used to determine saccharides formed and the molecular weight (Mw) distributions of the residual starch structure, respectively. Chain length (CL) distributions of debranched starch samples were further related to amylopectin (AP) retrogradation. Differential scanning calorimetry (DSC) results showed the complete inhibition of retrogradation when starches were hydrolyzed to >20% DH. Mw and CL distributions of residual AP structure indicated that with an increase in %DH, a higher proportion of unit chains with degree of polymerization (DP) ≤9 and a lower proportion of unit chains with DP ≥17 were formed. A higher proportion of short outer AP chains that cannot participate in the formation of double helices supports the decrease in and eventual inhibition of retrogradation observed with the increase in %DH. These results suggest that the maltogenic amylase could play a powerful role in inhibiting the staling of baked products even at limited starch hydrolysis.
authors.affiliation: †Department of Grain Science and Industry, Shellenberger Hall, Kansas State University, Manhattan, Kansas 66506, United States.
authors.forename: Navneet
authors.initials: N
authors.lastname: Grewal
authors.affiliation: †Department of Grain Science and Industry, Shellenberger Hall, Kansas State University, Manhattan, Kansas 66506, United States.
authors.forename: Jon
authors.initials: J
authors.lastname: Faubion
authors.affiliation: §Corbion, 7905 Quivira Road, Lenexa, Kansas 66215, United States.
authors.forename: Guohua
authors.initials: G
authors.lastname: Feng
authors.affiliation: #Center for Grain and Animal Health Research, Agricultural Research Service, U.S. Department of Agriculture, 1515 College Avenue, Manhattan, Kansas 66502, United States.
authors.forename: Rhett C
authors.initials: RC
authors.lastname: Kaufman
authors.affiliation: #Center for Grain and Animal Health Research, Agricultural Research Service, U.S. Department of Agriculture, 1515 College Avenue, Manhattan, Kansas 66502, United States.
authors.forename: Jeff D
authors.initials: JD
authors.lastname: Wilson
authors.affiliation: †Department of Grain Science and Industry, Shellenberger Hall, Kansas State University, Manhattan, Kansas 66506, United States.
authors.forename: Yong-Cheng
authors.initials: YC
authors.lastname: Shi
mesh_terms: D000687:Amylopectin / Q000737:chemistry*; D002152:Calorimetry, Differential Scanning; D006868:Hydrolysis; D008970:Molecular Weight; D003313:Zea mays / Q000737:chemistry*; D000516:alpha-Amylases / Q000737:chemistry*
chemical_list: D000687:Amylopectin; D000516:alpha-Amylases
keywords: chain length distribution; degree of hydrolysis; maltogenic amylase; molecular size distribution; retrogradation