Effect of saliva composition and flow on inter-individual differences in the temporal perception of retronasal aroma during wine tasting.

In order to determine if inter-individual differences in saliva composition and flow influence the perception of specific aromatic stimuli elicited by esters after wine consumption, ten individuals were selected and instructed in the recognition of four aromatic stimuli elicited by four ester compounds, which were added to a rosé wine. The whole panel was firstly characterised by their salivary flow, composition (pH, total protein content, macro- and micro- minerals) and rheological properties (viscosity), and secondly, the panellists were trained in a dynamic sensory method for the evaluation of retronasal aroma intensity at discrete time intervals (5, 60, 120, and 180 s) after wine expectoration. Significant inter-individual differences (p < 0.05) in saliva composition were found in most salivary parameters. Differences in the intensity ratings among individuals were also found for the four aroma attributes. Spearman correlation analysis between saliva parameters and aroma intensity over time showed a strong positive correlation between salivary flow and aroma perception for some aroma and time points. This correlation was higher in the immediate than in the long lasting perception and greater for aroma attributes elicited by short chain length esters (isoamyl acetate, ethyl butanoate and ethyl hexanoate) (than for attributes elicited by larger esters (ethyl decanoate).