Measurement of aroma compound self-diffusion in food models by DOSY

Self-diffusion measurement of solutes in polymer gels has been investigated using pulsed gradient spin echo NMR spectroscopy. However, few data are available on the self-diffusion of small solutes in natural polysaccharide polymers used as thickeners in the food industry. Since aroma diffusion in food matrices could have an impact on flavor release, this is an interesting and economic challenge. Diffusion ordered spectroscopy (DOSY) resolves diffusion data for each component in complex mixtures. We used DOSY with the inverse Laplace transform approach with the maximum entropy algorithm to investigate diffusion of two aroma compounds, ethyl butanoate and linalool, in an iota-carrageenan matrix as the food model. We showed that the self-diffusion coefficient values of small molecules in a polysaccharide matrix could be easily extracted using this method. We then investigated the impact of the gelling state of iota-carrageenan matrices on the self-diffusion of ethyl butanoate.