Role of saliva on wine aroma release by using in vitro static and dynamic headspace conditions

Abstract

Unlike other food products, the number of studies regarding aroma release during wine consumption using in vitro or in vivo approaches is very scarce, and research on the role of different intra-oral factors (such as saliva), which might be involved in aroma release during wine drinking is still incipient (1). Although the relatively short-intra-oral period of consumption of liquid foods, could indicate a limited effect of saliva on aroma release, the formation of intra-oral (and pharyngeal) aroma depots (2), and the fact that natural swallowing of saliva is continuously performed, makes the idea that saliva might exert an important role in the perception of wine aroma during consumption perfectly viable. However, only a couple of studies with contradictory results have attempted to determine the role of saliva on wine aroma release (3, 4). The fact that aroma release has been monitored using different extraction methodologies (static vs. dynamic headspace conditions) and others factors such as differences in matrix composition (ethanol, non-volatile wine matrix components) could also explain these differences.Therefore, the objective of this work was to determine the role of saliva on wine aroma release by using both static and dynamic headspace conditions. To follow a systematic study, avoiding the influence of different factors other than those of interest in this work (saliva effect and wine type) both methodologies were applied to reconstituted wines (with different non-volatile wine matrix composition) and a synthetic wine (with no matrix effect) keeping the same concentration of ethanol and aroma compounds. In addition, two types of saliva (human and artificial) and control samples (with water) were used to better understand the different mechanisms that saliva might induce on the release of aroma compounds from wine. Results from this work showed that in static conditions, red wines were more affected than white and synthetic wines by saliva, specifically human saliva, which provoked a reduction in aroma release for most of the assayed aroma compounds independent of their chemical structure. The application of dynamic headspace conditions using a saliva bioreactor at two different sampling points (t=0 and t=10 min) corresponding with oral (25.5 ºC) and post-oral phases (36 ºC), showed a lesser effect of saliva than matrix composition and a high influence of temperature on aroma release. (1) Munoz-Gonzalez, C.; Rodriguez-Bencomo, J. J.; Moreno-Arribas, M. V.; Pozo-Bayon, M. A. Anal. Bioanal. Chem. 2011, 401, 1497-1512.(2) Munoz-Gonzalez, C.; Martin-Alvarez, P. J.; Victoria Moreno-Arribas, M.; Angeles Pozo-Bayon, M.A J. Agr. Food Chem. 2014, 62, 66-73. (3) Genovese, A.; Piombino, P.; Gambuti, A.; Moio, L. Food Chem. 2009, 114, 100-107.(4) Mitropoulou, A.; Hatzidimitriou, E.; Paraskevopoulou, A. Food Res. Int. 2011, 44, 1561-1570