Magnetic Resonance in Food Science
A View to the Future
By G. A. Webb, P. S. Belton, A. M. Gil, I. DelgadilloThe Royal Society of Chemistry
Copyright © 2001 The Royal Society of Chemistry
All rights reserved.
ISBN: 978-0-85404-648-5Contents
A View Towards the Next Century,
Recent Advances in Solid-state NMR R. K. Harris, 3,
Characterisation of Meat Structure by NMR Imaging at High Field J. M. Bonny, W. Laurent and J. P. Renou, 17,
MRI Indicators for Measuring pH and Redox in Food S. D. Evans and L. D. Hall, 22,
Rheo-NMR of Carrageenan Gels and Sols P. T. Callaghan and A. M. Gil, 29,
An Insight into the Structure of Foods Using 13C and 1H Magic Angle Spinning (MAS) NMR: Application to Wheat Dough A. M. Gil, E. Alberti and D. Santos, 43,
Hyphenated Methods in NMR M. Spraul, V. Braumann, M. Godejohann and M. Hofmann, 54,
Relationships between Sensory Texture of Soft Cheese and MRI Measurements F. Mariette, G. Collewet, P. Fortier and J. M. Soulie, 67,
Mannitol Production by a Genetically Modified Lactococcus Lactis Strain Studied by 13C NMR In Situ A. R. Neves, A. Ramos and H. Santos, 75,
Food Safety and Health,
MRI of Gastric Function P. A. Gowland, L. Marciani, A. Fillery-Travis and R. C. Spiller, 85,
Detection of Free Radicals in γ-Irradiated Soybean Paste by Electron Spin Resonance Spectroscopy E. J. Lee, V. I. Volkov and C. H. Lee, 98,
Supression Effects of Spice Plants on Free Radical Formation B. L. Milic, S. M. Djilas and N. B. Milic, 105,
NMR Studies on the Antiradical Mechanism of Phenolic Compounds Towards 2,2-Diphenyl-1-picrylhdrazyl Radical A. M. S. Silva, C. M. M. Santos, J. A. S. Cavaleiro, H. R. Tavares, F. Borges and F. A. M. Silva, 110,
Natural Antioxidants and Free Radicals – an ESR Perspective C. Chen, H.-R. Tang and P. S. Belton, 117,
Oleuropein Biomimetic Conformations by Magnetic Resonance Experiments and Molecular Mechanics and Dynamics F. Capozzi, M. A. Cremonini, N. Russo, E. Tocci and N. Uccella, 129,
Isolation and trans-Resveratrol Analysis in Brazilian Red Wine by 1H Nuclear Magnetic Resonance M. Maraschin, R. Passos, J. M. O. Duarte da Silva, P. F. Dias, P. S. Araujo, A. C. Oltramari, J. D. Fontana and M. S. B. Caro,
Structure and Dynamics,
Fast Field Cycling NMR – Applications to Food P. S. Belton and Y. Wang, 145,
Starch Granules – A Multinuclear Magnetic Resonance Study H. Tang and B. Hills, 155,
Restricted Diffusion in the Lecithin-Water System M. M. Doroginizkij and A. V. Filipov, 165,
Molecular Mobility in Frozen Sugar Solutions D. Martin, S. Ablett and M. Izzard, 172,
Interpreting Near Infard Spectra of Solutions by Outer Product Analysis with Time Domain-NMR D. N. Rutledge, A. S. Barros and R. Giangiacomo, 179,
Interaction of β-Casein at an Emulsion Interface Studied by 2H NMR and Molecular Modeling J. A. G. Areas, M. M. Cassiano, C. Glaubitz, G. Groebner and A. Watts, 193,
Slicing – A Novel Approach for Unique Deconvolution of NMR Relaxation Decays H. T. Pedersen, R. Bro and S. B. Engelsen, 202,
Analysis, Monitoring and Authentication,
High Resolution NMR of Virgin Olive Oil R. Sacchi, 213,
Origin Recognition of Wild and Farmed Salmon (Norway and Scotland) Using 13C NMR Spectroscopy in Combination with Pattern Recognition Techniques M. Aursand and D. E. Axelson, 227,
High Resolution NMR Studies of Meat Composition and Authenticity O. Al-Jowder, F. Casuscelli, M. Defernez, E. K. Kemsley, R. H. Wilson and I. J. Colquhoun, 232,
Magnetic Resonance Imaging to Classify Loin from Iberian Pig E. Cernadas, T. Antequera, P. G. Rodriguez, M. L. Duran, R. Gallardo and D. Villa, 239,
Industrial Magnetic Resonance – Food and Other Industries A. De Los Santos, J. D. King and D. C. Stead, 246,
Magnetic Resonance Imaging as a Tool to Quantify the Adiposity Distribution in Fish G. Collewett, C. Toussaint, A. Davenel, S. Akoka, F. Medale, B. Fauconneau and P. Hagray, 252,
An NMR Study of the Biochemistry of Mango: The Effects of Ripening, Processing and Microbial Growth I. F. Duarte, I. Delgadillo, M. Spraul, E. Humpfer and A. M. Gil, 259,
Subject Index, 267,
CHAPTER 1
RECENT ADVANCES IN SOLID-STATE NMR
Robin K. Harris
Department of Chemistry,
University of Durham,
South Road,
Durham, DH1 3LE, U.K.
1 INTRODUCTION
Since the first successful use of the now-common combination of techniques (cross polarisation, magic-angle spinning ,and high-power proton decoupling) in 1976, NMR has transformed our ability to obtain structural and mobility information at the molecular level in a wide range of solids. Its value was first exploited for polymers and for zeolites but is now applied to all branches of chemistry and has spread to areas such as earth sciences, molecular biology – and food science. The recent expansion in applications has been sparked by new developments in techniques, especially in the use of a wide variety of specialised pulse sequences. Indeed, solid-state NMR now rivals, or even exceeds, solution-state NMR in its complexity. In principle, more information is available from NMR for solids than for solutions because anisotropic interactions (such as shielding, dipolar coupling and quadrupolar coupling) have more direct effects on spectra in the former case because there is less averaging from mobility at the molecular level.
The objective of this article is to introduce some of the important themes in modem solid-state NMR and to illustrate some applications, mostly using examples studied at Durham. Obviously, in a short article one has to be highly selective, and the choice of topics of importance is both personal and subjective. The article does not address food science matters directly, but the issues it raises do have relevant substantial consequences in this area. There is no doubt that the topics mentioned herein will find substantial applications in food science studies in the coming decade.
To start with, it is pertinent to point out the complementarity of diffraction techniques and solid-state NMR. The former rely on full three-dimensional long-range order for their optimum use, whereas NMR is sensitive to the local environment. The multinuclear aspect of magnetic resonance is very important: the method is isotope-specific, and there is never any problem of knowing which nucleus is being accessed. This means it can clearly distinguish between, say, nitrogen and oxygen, thus often providing information on disorder in crystalline lattices in cases where the placement of isoelectronic atoms may cause some difficulties for diffraction. Some simple crystallographic information, such as knowledge of the asymmetric unit, may be readily provided by NMR, which on occasion may give initial assistance to full crystal structure determination from diffraction experiments. Above all, NMR functions efficiently for microcrystalline "powder" samples. Although additional information may be obtained for single crystals by NMR this is largely of a rather esoteric nature. NMR spectra are sensitive to the form of crystalline solids and can therefore be readily used to study polymorphism and phase transitions. NMR is of substantial value for both amorphous and heterogeneous materials (which are, of course, ubiquitous in food materials), so that useful chemical and physical microstructure information can be obtained, particularly in the latter case because discriminating pulse sequences can be applied to...
