In food science and technology, assessment of phase-compositional behaviour of lipids is critical for understanding many product properties and for effective process control. Time Domain NMR is a rapid and easy-to-handle technique, and is already well appreciated as a tool for phase-compositional assessment in foods. The phase-compositional detail that can be obtained with the established methodology is limited, however. In this work, we set out to obtain more phase-compositional details of lipids as currently feasible with the already established 'classical' NMR methods. We deployed a combined FID-CPMG experiment, and analyzed the Transversal Relaxation Decays by Deconvolution (TRDD) with semi-empirical mathematical functions for solid, semi-solid and liquid components. Within the solid component, different lipid crystal polymorphs can be discerned in a quantitative manner, i.e. alpha, beta and beta'. The TRDD method was validated against established NMR SFC methods, in terms of accuracy ('trueness') and precision. The solid fat content (SFC) of a large collection of fat blends was measured by the commonly employed NMR Direct and Indirect SFC methods and a good correlation with the results of the TRDD was observed, thereby demonstrating accuracy. Furthermore, TRDD was found to be equally precise as the established NMR SFC methods.

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Syndiotactic polystyrene clathrates hosting benzene‐d6 or toluene‐d8 molecules in the cavities of the δ crystalline form have been prepared and investigated by means of solid state 2H NMR spectroscopy. Benzene‐d6 molecules were found to be involved in a fast rotation about the C6 symmetry axis whereas the toluene‐d8 molecules exhibit a fast rotation of the methyl group about the symmetry axis passing through the C1 and C4 carbon atoms.

A rapid benchtop NMR method for determination of droplet size distributions in food emulsionsThe determination of water and oil droplet size distributions in food emulsions by lowfield NMR has the advantage of a simple and non-perturbing sample preparation. Furthermore, NMR performs very well with respect to precision. The current implementation on most benchtop NMR spectrometers deploys a variation of gradient duration and requires continuous corrections for gradient imbalances, thus making the whole procedure a time-consuming one. By using variation of gradient strength and further stretching the capability of commercial benchtop NMR spectrometers, both water and oil droplet sizes can be measured in a more rapid manner, typically two to three times faster. The measured droplet size distributions are equivalent to those assessed by the current (slow) method, for both O/W and W/O emulsions. Furthermore, the rapid method shows a good performance with respect to precision. In addition, the method is able to determine droplet sizes in samples with much smaller amounts of dispersed phase.

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