Dynamics of Arabic gum aqueous solutions as revealed by NMR relaxometry

J Sci Food Agric. 2022 Oct;102(13):5808-5813. doi: 10.1002/jsfa.11930. Epub 2022 Apr 30.

Abstract

Background: The purpose of this article is to study molecular dynamics through nuclear magnetic relaxation (NMR) dispersion of Arabic gum aqueous solutions analysed in terms of two-fraction exchange model.

Results: The experiments revealed that relaxation of water molecules was non-monoexponential, which was interpreted in terms of a model describing the magnetization transfer due to exchange of water and polysaccharide protons. The analysis showed that water dynamics decreased slightly with gum content. Polymer-chain dynamics was assigned to regime II of the tube/reptation model. Peculiar temperature dependence of exchange rate was observed in the whole concentration range of Arabic gum solutions.

Conclusion: NMR relaxation probed in a broad frequency and temperature range allows probing of the molecular dynamics of complex food systems. © 2022 Society of Chemical Industry.

Keywords: Arabic gum; NMR relaxometry; exchange interactions; molecular dynamics; polysaccharides.

MeSH terms

  • Gum Arabic / chemistry
  • Physical Phenomena
  • Polysaccharides
  • Protons*
  • Temperature
  • Water*

Substances

  • Polysaccharides
  • Protons
  • Water
  • Gum Arabic