Role of oral mucosa on aroma release and aroma persistence after wine intake

Abstract

Aroma is one of the main attributes of wine quality and it is an outstanding aspect related to food preferences and choices. In recent years, an innovative research on flavor chemistry is focused on what happen with aroma molecules during food intake. This type of research is generating new insights on the important role of individual physiology in the way aroma molecules are released within the oral cavity during food intake and how these compounds interact with the olfactory receptors (Buettner & Beauchamp, 2010). Among different oral physiological factors, oral mucosa might have an outstanding role in the interaction and release of wine aroma after wine intake. This phenomenon can be related to the aroma persistence (or after-odour) which is defined as a long lasting aroma perception of wine odorants after swallowing. This phenomenon is very often related to wine aroma quality. Recent research performed in our lab suggests that wine matrix composition might be involved in the capacity of oral mucosa to adsorb aroma molecules (Muñoz-González et al., 2014); however, this hypothesis needs to be confirmed. Therefore, the objective of this work has been to evaluate the role of oral mucosa to adsorb and release aroma compounds after wine intake employing in vivo conditions and the effect of wine matrix composition in this ability. To determine the amount of aroma adsorbed to oral mucosa after wine intake, a methodology based in the Spit Off Odorant Measurement was developed. With this technique, the percentage of aroma retained in the mucosa was determined by difference between the amount of aroma in the original wine and the amount of aroma recovered in the expectorated wine. In addition, to evaluate the aroma released from oral mucosa, which is more related to oral persistence, an intra-oral HS-SPME-GCMS methodology allowing the in vivo aroma monitoring was also optimized. Results from this work confirmed that oral mucosa is able to interact with aroma compounds, which depends on the time the wine is retained within the oral cavity and on the physical-chemical characteristics of the aroma compounds. In addition, oral mucosa released the aroma compounds progressively after wine consumption, which can be related with aroma persistence after wine intake. This property is dependent on physiological differences among individuals (e.g. breathing flows). The experiments performed by using commercial wines with different winemaking technology (red, white, rosé) and experimental wines with different composition, showed that wine matrix composition, and especially, wine polyphenols, can be important contributors to aroma retention in the oral mucosa. These compounds seem to act as aroma reservoirs being involved on the progressive aroma release after the consumption of certain wines.