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Interactions between phenol and cationic cetyltrimethylammonium bromide (CTAB) micelles have been investigated by means of nuclear magnetic resonance spectroscopy. The combined use of 1 H and NOESY techniques revealed that phenol has different preferred locations of interaction depending on the pH. At neutral pH (6.70) conditions, phenol molecules are preferentially located in the outer micelle region, at the micelle-water interface, while at more basic pH (9.94), the deprotonated phenol molecules (C 6 H 5 O -) are immersed into the palisade layer of the micelle. In addition, quantitative estimates of the solubilized fraction of phenol were obtained by using PFG-NMR. The results indicate that the phenol-CTAB interactions, although already present in neutral pH conditions, are largely favored in basic conditions as a consequence of the strong electrostatic interaction between the negatively charged phenolate ions and the positive charge of the cationic surfactant head group.(e)

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Using the water diffusion data, the use of a low measurement temperature and diffusion delay Δ could reduce the droplet size overestimation resulting from extra-droplet water diffusion, but this undesirable effect was inevitable. Detailed analysis of the diffusion data revealed that the extra-droplet diffusion effect was due to an exchange between the inner water phase and the oil phase, rather than by exchange between the internal and external aqueous phase. A promising data analysis procedure for retrieving reliable size data consisted of the application of Einstein's diffusion law to the experimentally determined diffusion distances. This simple procedure allowed determining the inner water droplet size of W/O/W emulsions upon measurement of water diffusion by low-resolution NMR at or even above room temperature.

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2One of the main changes that occur during heat treatment of milk is whey protein denaturation, 3 which in its turn may lead to protein aggregation and gelation. In this contribution, the effect of 4 lysophospholipids, the main components of lysolecithins, as well as alternative surfactants, on 5 heat-induced whey protein aggregation has been studied. Hereby, attention was paid to the 6 relation between polar lipid molecular structure (e.g. effect of alkyl chain length, effect of polar 7 head group) and heat stabilising properties. Residual protein determination in the supernatant 8 obtained after centrifugation of heated whey protein solutions learned that whey protein 9 aggregation was at least partly prevented in the presence of surfactants. As the short alkyl chain 10 lysophospholipids were particularly effective heat stabilisers, hydrophilic surfactants seemed to 11 be most effective, which may be ascribed to their higher critical aggregation concentration. Upon