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Fitting of NMR Relaxation Decays of Sugar-Water Mixtures. M. v.d.Bosch 1 , W. Derbyshire 2 , D. v.Dusschoten 1 , I.A. Farhat 2 , W. MacNaughtan 2 , M.A. Hemminga 1 and J.R. Mitchell 2.
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Fitting of NMR Relaxation Decays of Sugar-Water Mixtures M. v.d.Bosch1, W. Derbyshire2, D. v.Dusschoten1, I.A. Farhat2 ,W. MacNaughtan2, M.A. Hemminga1 and J.R. Mitchell2 1Laboratory of Molecular Physics, Wageningen University, Dreijenlaan 3, PO Box 8128, 6700 ET Wageningen, The Netherlands 2Division of Food Science, School of Biological Science, University of Nottingham, Sutton Bonington Campus, Loughborough, Leic’s, LE12 5RD, United Kingdom
Introduction Problem • Molecular motion in sugar-containing glasses is important to understand physical properties such as crystallisation, rheology and effects of plasticisers Goal • Molecular motions are reflected by proton dipolar interactions • These interactions can be picked up by 1H NMR spectroscopy • The motion of the protons, mobile versus immobile, can be determined
FT Frequency domain Model Two component analysis: Immobile component fast slow + Time domain Mobile component Fit in time domain by:
Analysis of immobile component Dipolar interactions or 1) 2) Fit in time domain by: 1) Sinc fitting: broadening rectangle 2) Pake fitting: FT broadening Pake doublet
Conclusions Spectrum FID Fitting method FT
Interpretation • Selection of analysis model in 1H NMR of sugar-water systems is crucial • Mobile (B) and immobile (A) proton fractions can be well-characterized • Distribution of pake patterns needs further evaluation