title: Effect of high hydrostatic pressure on the supramolecular structure of corn starch with different amylose contents.
abstract: Corn starches with amylose contents ranging from 0 to 80% were suspended in 60 wt% water or ethanol and subjected to high hydrostatic pressure (HHP) up to 600 MPa. The impact of HHP treatment on the granule morphology, lamellae structures, and crystalline characteristics were examined with a combination of SAXS, WAXS and optical microscopy. All starch dispersed in water showed a decrease in area of the lamellar peak in the SAXS data at q∼0.6 nm(-1). The lamellae thickness (d) increased for pressurized waxy, normal, and Gelose80 corn starches, suggesting water is forced into starch lamellae during HHP. However, for Gelose50 corn starch, the d remained constant over the whole pressure range and light microscopy showed no obvious granule swelling. WAXS studies demonstrated that HHP partially converted A-type starches (waxy and normal corn) to starches with a faint B-type pattern while starches with a B+V-type pattern (Gelose50 and Gelose80), were not affected by HHP. All corn starches suspended in ethanol showed no detectable changes in either granule morphology, or the fractal, the lamellae, and the crystalline structures.
authors.affiliation: School of Chemical Sciences, The 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, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand.
authors.forename: Peter
authors.initials: P
authors.lastname: Swedlund
authors.affiliation: School of Chemical Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand; The Riddet Institute, Palmerston North, New Zealand. Electronic address: y.hemar@auckland.ac.nz.
authors.forename: Yacine
authors.initials: Y
authors.lastname: Hemar
authors.affiliation: Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, China.
authors.forename: Guang
authors.initials: G
authors.lastname: Mo
authors.affiliation: Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, China.
authors.forename: Yanru
authors.initials: Y
authors.lastname: Wei
authors.affiliation: Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, China.
authors.forename: Zhihong
authors.initials: Z
authors.lastname: Li
authors.affiliation: Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, China.
authors.forename: Zhonghua
authors.initials: Z
authors.lastname: Wu
mesh_terms: D000688:Amylose / Q000737:chemistry*; D006874:Hydrostatic Pressure; D015394:Molecular Structure; D053838:Scattering, Small Angle; D013213:Starch / Q000737:chemistry*; D014961:X-Ray Diffraction; D003313:Zea mays / Q000737:chemistry*
chemical_list: D013213:Starch; D000688:Amylose
keywords: Corn starch; Different amylose content; High hydrostatic pressure (HHP); SAXS/WAXS