Physicochemical properties of partially α-glucan-coated normal corn starch formed by amylosucrase from Neisseria polysaccharea

Int J Biol Macromol. 2019 Jul 15;133:1102-1106. doi: 10.1016/j.ijbiomac.2019.04.133. Epub 2019 Apr 17.

Abstract

Amylosucrase (AS) is a glycosyltransferase that produces linear α-1,4 glucans using sucrose as the sole substrate. In this study, for various applications, α-glucan-coated starch (α-GCS) was produced by AS (20 U/Lreactant) from Neisseria polysaccharea to improve the physicochemical properties of raw normal corn starch (NCS) by applying different reaction conditions (i.e., varying the substrate concentration, pH, and temperature). Field-emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD) showed that raw NCS was successfully coated by α-glucan. Differential scanning calorimetry (DSC) and rapid viscosity analyses (RVA) of the α-GCS confirmed that the α-glucan coating decreased the degree of retrogradation. Notably, compared to raw NCS as a control, starch retrogradation was significantly (p < 0.05) decreased by 13.7% after five weeks. Therefore, the novel α-GCS can be applied as a functional material for controlled retrogradation in the starch-based food industry for shelf-life extension.

Keywords: Amylosucrase; Retrogradation; Starch coating.

MeSH terms

  • Chemical Phenomena*
  • Food Storage
  • Glucans / chemistry*
  • Glucosyltransferases / metabolism*
  • Neisseria / enzymology*
  • Solubility
  • Starch / chemistry*

Substances

  • Glucans
  • Starch
  • Glucosyltransferases
  • amylosucrase