Wine compounds' role on mouthfeel perception

Resumen del trabajo presentado al Wine Active Compounds (WAC), celebrado en Beaune (Francia) del 29 al 31 de marzo de 2017.Wine creates a group of oral-tactile stimulations not related to taste or aroma, such as astringency or fullness. This work aims to understand the role of wine components in mouthfeel perception. Eight different model wines with/without ethanol (8%), glycerol (10 g/L) and tannins (1 g/L) were studied. A panel of thirteen assessors was trained to perform a descriptive sensory assessment. The descriptors used by the trained sensory panel were divided into the visual phase (sediment, colour, viscosity), in the mouth phase (sweetness, acidity, bitterness, wood taste, astringency, dryness, earthiness, hotness mouthfeel, alcoholic feeling, viscosity) and after taste (global and alcohol persistence, wood aftertaste). The physical origin of the perceived changes were study through rheology (rheometer, Malvern, UK), and tribology (MTM machine PCS, UK). To study the proteins changes and its relation with astringency, dynamic light scattering and Fourier transform infrared spectroscopy (FTIR) were used. Statistical analysis was done to study the sensory differences among wine and its relation to instrumental analysis. Ethanol presence was related to the hotness mouthfeel, alcohol persistence, and feeling; ethanol also increases the intensity of other attributes. The presence of tannins was related to the intensity of colour, astringency, and dryness, the presence of ethanol did not hide this mouthfeel, having a synergetic effect. Instrumental results showed an increment of viscosity in presence of saliva, and a bulk effect in presence of wine components. The presence of tannin differentiates the samples colour, increased the z-average diameter of the saliva and FTIR bands were also affected. The evolution of friction as a function of entrainment velocity and sliding distance was observed and correlated with sensory and rheological measurements. More understanding of mouthfeel sensory perception and instrumental characterization will allow better understanding of wine quality.Peer reviewe