Contribution of non-volatile and aroma fractions to in-mouth sensory properties of red wines: Wine reconstitution strategies and sensory sorting task

This work explores to what extent the aroma or the non-volatile fractions of red wines are responsible for the overall flavor differences perceived in-mouth. For this purpose, 14 samples (4 commercial and 10 reconstituted wines), were sorted by a panel of 30 trained assessors according to their sensory in-mouth similarities. Reconstituted wines were prepared by adding the same volatile fraction (coming from a red wine) to the non-volatile fraction of 10 different red wines showing large differences in perceived astringency. Sorting was performed under three different conditions: (a) no aroma perception: nose-close condition (NA), (b) retronasal aroma perception only (RA), and (c) allowing retro- and involuntary orthonasal aroma perception (ROA). Similarity estimates were derived from the sorting and submitted to multidimensional scaling (MDS) followed by hierarchical cluster analysis (HCA). Results have clearly shown that, globally, aroma perception is not the major driver of the in-mouth sensory perception of red wine, which is undoubtedly primarily driven by the perception of astringency and by the chemical compounds causing it, particularly protein precipitable proanthocyanidins (PAs). However, aroma perception plays a significant role on the perception of sweetness and bitterness. The impact of aroma seems to be more important whenever astringency, total polyphenols and protein precipitable PAs levels are smaller. Results also indicate that when a red-black fruit odor nuance is clearly perceived in conditions in which orthonasal odor perception is allowed, a strong reduction in astringency takes place. Such red-black fruit odor nuance seems to be the result of a specific aroma release pattern as a consequence of the interaction between aroma compounds and the non-volatile matrix.

The clustering of 12 red wines according to the non-volatile chemical composition (left plot) and to a sorting task performed by a group of 35 trained panelists asked to group wines according to in-mouth similarities (right plot) are equivalent. The chemical parameters protein precipitable proanthocyanidins (PAs) and total phenolic content, linked to astringency, are the main drivers of global in-mouth perception in red wines.Figure optionsDownload as PowerPoint slideHighlights
► Aroma perception is not a major driver of the in-mouth sensory perception of red wine.
► The chemical compounds causing astringency (mainly precipitable PAs) drive in-mouth perception.
► The role of aroma is more important whenever astringency, total phenols and PAs levels are smaller.
► When a red-black fruit odor nuance is clearly perceived, a strong reduction in astringency occurs.
► Aroma release patterns depend on the interaction between aroma compounds and the non-volatile matrix.