Investigations of food colloids by NMR and MRI

Abstract

Since the publication of the ISO method for measurement of solid fat content using NMR relaxation at low field, the application of this technique to the characterisation of food composition and food structure on several length scales has expanded considerably.Improvements in the electronic and computational specifications of NMR spectrometers and the use of more sophisticated signal processing methods have led to several new applications, and NMR, previously recognized as a powerful technique to provide information regarding composition, is now widely used for microstructural investigations. Moreover, MRI applications have in recent years been extended from the medical field to food science and this has opened up new opportunities for the understanding of food. We examine here recent developments in these techniques, including NMR relaxation, multidimensional NMR relaxation, diffusion NMR and MRI.

Water Mobility and Distribution in Green Coffee Probed by Time-Domain Nuclear Magnetic Resonance

“…3,4 In recent years, time-domain nuclear magnetic resonance (TD-NMR) has emerged as a very effective and unique tool to probe cellular compartmentation of water in heterogeneous systems such as biological tissues and food matrices. [5][6][7][8][9][10][11] The advantages of TD-NMR, of being a noninvasive technique and requiring no sample preparation, largely compensate its intrinsic low sensitivity. By measuring transverse relaxation time constants (T 2 ) extracted from NMR relaxometry experiments, it is possible to distinguish between different states of water embedded in complex biological systems in terms of different proton mobilities.…”

Rapid sphere sizing using a Bayesian analysis of reciprocal space imaging data

“…In recent years a number of nuclear magnetic resonance (NMR) techniques have been used to characterise the SSD in foams/emulsions and there is currently an expanding activity in this area [6,21,22]. The majority of the approaches have exploited pulsed field gradient (PFG) NMR techniques which measure molecular self-diffusion.…”

Olive oil and hyperthermal water bigels for cosmetic uses

“…Owing to its non-invasive nature, and ability to probe structures over a broad range of length scales, NMR has established itself as a tool for the structural characterisation of anisotropic domain sizes in liquid crystals [19], fluctuations in ordered lamellar phases under weak shear [20] and the sizing of shear-induced multi-lamellar vesicles [21,22]. It was also used for cosmetic emulsions [23] and food emulsions [24][25][26][27] characterisation. With respect to two-phase systems, NMR offers a variety of unique insights into both molecular orientation and transport kinetics within the various phases.…”