6533b82dfe1ef96bd1291fff
RESEARCH PRODUCT
Structure of calcium and zinc pectinate films investigated by FTIR spectroscopy
Philippe CayotOdile ChambinAli AssifaouiCamille Loupiacsubject
food.ingredientPectinCoordination numberInorganic chemistrychemistry.chemical_elementZincCalciumBiochemistryAnalytical ChemistryDialysis tubingchemistry.chemical_compoundfoodX-Ray DiffractionAmideSpectroscopy Fourier Transform InfraredCarboxylateFourier transform infrared spectroscopyFilmChemistryOrganic ChemistryGeneral MedicinePectin[SDV.BBM.BP]Life Sciences [q-bio]/Biochemistry Molecular Biology/BiophysicsZincFTIR spectroscopyMicroscopy Electron ScanningPectinsCalcium[SDV.AEN]Life Sciences [q-bio]/Food and Nutritiondescription
International audience; Calcium and zinc pectinate gels were prepared using a method which allowed calcium or zinc to diffuse from the cross-linking solution through a dialysis membrane to form a gel with amidated low-methoxyl pectin. The gel thus obtained was then dried, and the film structure was studied using FTIR spectroscopy as a function of the cation content (0%, 5%, 10%, and 15% w/v). Important consideration was given to the three functional groups (amide, carboxyl ester, and carboxylate groups) present in the pectin. When the zinc content was increased, the three wavenumber values corresponding to these three functional groups did not change significantly, while for calcium pectinate, the three wavenumber values were shifted profoundly when the amount of calcium ions changed. These results confirm that calcium ions could form stable interactions with carboxylate groups as described by the eggbox model [Grant, G.T.; Morris, E.R.; Rees, D.A.; Smith, P.J.C.; Tho, D. FEBS Lett.1973, 32, 195–198] while the lower coordination number of zinc does not permit a structured gel to develop.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2010-05-01 |