The effect of solution surface tension on aroma compound release from aqueous xanthan solutions

This study aimed to elucidate the mechanisms governing the release of limonene from model matrices in aqueous xanthan solutions. The aroma compound release behaviour from the matrices has been linked with both the rheological and the surface tension properties of the solutions. Considering the limonene release as a function of the polymer concentration regime, a significant rise in limonene retention is observed above the critical overlap concentration, C*, of the biopolymer. Increasing the amount of xanthan involves a marked decrease in limonene release until the concentrated regime is reached (above C**), at which the limonene release is constant whatever the polymer content. In parallel, solution surface tension properties allow us to state the establishment of intra- and intermolecular non-polar interactions of xanthan molecules above C*. As such molecular interaction may explain the change in limonene behaviour, these preliminary results contribute to a better understanding of the phenomena governing the retention/release of the volatile from such xanthan-containing media. Copyright (c) 2006 John Wiley & Sons, Ltd.