Water Dynamics in Whey-Protein-Based Composite Hydrogels by Means of NMR Relaxometry

ÖZEL B., Kruk D., Wojciechowski M., Osuch M., Oztop M. H.

INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES, vol.22, no.18, 2021 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 22 Issue: 18
  • Publication Date: 2021
  • Doi Number: 10.3390/ijms22189672
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, CAB Abstracts, EMBASE, Food Science & Technology Abstracts, MEDLINE, Veterinary Science Database, Directory of Open Access Journals
  • Keywords: nuclear magnetic resonance, relaxation, hydrogels, whey protein, diffusion, dynamics, ANTHOCYANINS, RELAXATION, RELEASE, GUM, PERSPECTIVES, DIFFUSION, KINETICS, RHEOLOGY, DIETARY
  • Middle East Technical University Affiliated: Yes


Whey-protein-isolate-based composite hydrogels with encapsulated black carrot (Daucus carota) extract were prepared by heat-induced gelation. The hydrogels were blended with gum tragacanth, pectin and xanthan gum polysaccharides for modulating their properties. H-1 spin-lattice relaxation experiments were performed in a broad frequency range, from 4 kHz to 30 MHz, to obtain insight into the influence of the different polysaccharides and of the presence of black carrot on dynamical properties of water molecules in the hydrogel network. The H-1 spin-lattice relaxation data were decomposed into relaxation contributions associated with confined and free water fractions. The population of the confined water fraction and the value of the translation diffusion coefficient of water molecules in the vicinity of the macromolecular network were quantitatively determined on the basis of the relaxation data. Moreover, it was demonstrated that the translation diffusion is highly anisotropic (two-dimensional, 2D).