Steady and dynamic shear rheology of sweet potato starch-xanthan gum mixtures

Hae M. Choi, Byoungseung Yoo

Research output: Contribution to journalArticlepeer-review

88 Scopus citations

Abstract

The effect of xanthan gum at different concentrations (0.2-0.6% w/w) on the rheological properties of sweet potato starch (SPS) pastes was evaluated under steady and dynamic shear conditions. The presence of xanthan resulted in an increase in the consistency index and vane yield stress of SPS. The effect of temperature on the apparent viscosity of SPS-xanthan mixtures is well described by the Arrhenius equation. Dynamic moduli (G′, G″, and η*) values of the mixtures increased with an increase in xanthan concentration while the tan δ values decreased. The addition of xanthan appeared to contribute to the elastic properties of the weak network of the SPS pastes. The structure development rate constant (k) of gelation during ageing was strongly influenced by the presence of xanthan. This suggests that the phase separation process caused by the incompatibility phenomena between the amylose component in starch and xanthan can increase the elastic characteristics of the SPS-xanthan mixtures.

Original languageEnglish
Pages (from-to)638-643
Number of pages6
JournalFood Chemistry
Volume116
Issue number3
DOIs
StatePublished - 1 Oct 2009

Keywords

  • Dynamic property
  • Gelation
  • Rheology
  • Sweet potato starch
  • Vane yield stress
  • Xanthan gum

Fingerprint

Dive into the research topics of 'Steady and dynamic shear rheology of sweet potato starch-xanthan gum mixtures'. Together they form a unique fingerprint.

Cite this