title: Retrogradation of Maize Starch after High Hydrostatic Pressure Gelation: Effect of Amylose Content and Depressurization Rate.
abstract: High hydrostatic pressure (HHP) has been employed to gelatinize or physically modify starch dispersions. In this study, waxy maize starch, normal maize starch, and two high amylose content starch were processed by a HHP of the order of 600 MPa, at 25°C for 15min. The effect of HHP processing on the crystallization of maize starches with various amylose content during storage at 4°C was investigated. Crystallization kinetics of HHP treated starch gels were investigated using rheology and FTIR. The effect of crystallization on the mechanical properties of starch gel network were evaluated in terms of dynamic complex modulus (G*). The crystallization induced increase of short-range helices structures were investigated using FTIR. The pressure releasing rate does not affect the starch retrogradation behaviour. The rate and extent of retrogradation depends on the amylose content of amylose starch. The least retrogradation was observed in HHP treated waxy maize starch. The rate of retrogradation is higher for HHP treated high amylose maize starch than that of normal maize starch. A linear relationship between the extent of retrogradation (phase distribution) measured by FTIR and G* is proposed.
authors.affiliation: School of Chemical Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Yang
authors.affiliation: School of Chemical Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand.
authors.forename: Peter
authors.initials: P
authors.lastname: Swedlund
authors.affiliation: Australian Synchrotron, 800 Blackburn Rd., Clayton 3168, Australia.
authors.forename: Qinfen
authors.initials: Q
authors.lastname: Gu
authors.affiliation: School of Chemical Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand.
authors.forename: Yacine
authors.initials: Y
authors.lastname: Hemar
authors.affiliation: Division of Biological and Environmental Science and Engineering, KAUST, Thuwal, 23955, KSA.|Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Mailstop 6R-2100. Berkeley, CA, 94720, United States of America.
authors.forename: Sahraoui
authors.initials: S
authors.lastname: Chaieb
mesh_terms: D000688:Amylose / Q000032:analysis*; D002152:Calorimetry, Differential Scanning; D003460:Crystallization; D006874:Hydrostatic Pressure; D012212:Rheology; D017550:Spectroscopy, Fourier Transform Infrared; D013213:Starch / Q000737:chemistry*; D003313:Zea mays / Q000737:chemistry*
chemical_list: D013213:Starch; D000688:Amylose