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• Tannin and anthocyanin fractions were isolated from a diverse set of 20 red wines. • Sensory analysis of fractions was conducted with sorting task and rate- K attributes. • "Bitter" and "dry" were salient attributes differing among anthocyanic fractions. • Anthocyanic fraction contributes to orosensory cues more than previously thought. • Red wine was proposed to contain strong bitterness suppressors. Tannins and anthocyanins are important modulators of the intrinsic quality of red wines, playing a major role in consumer preference and appreciation. Tannins are chiefly responsible for the astringency in wines although their role in eliciting different astringent subqualities is still relatively unknown. On the other hand, the sensory contribution of anthocyanic fractions is even less clear. The main aim of the present study was to assess whether anthocyanic fractions from red wine elicit specific mouthfeel and taste attributes that differ from their tannin counterparts, and to evaluate the contribution of anthocyanic and tannic fractions to taste and mouthfeel of red wines. Isolation of tannin (F tannin) and anthocyanin (F antho) fractions from 20 wines involved reversed-phase semipreparative liquid chromatography followed by solid phase extraction. The 40 derived fractions subsequently underwent sensory characterisation using a labelled sorting task and a rate- K attributes method. Bitterness and dryness were the salient attributes differing among the sensory spaces of both F antho and F tannin. Likewise, other independent and non-correlated mouthfeel dimensions differed for both F antho ("grainy" and mouthcoating") and F tannin ("gummy"). A significant linear model predicting wine dryness from the "dry" intensity of F antho and F tannin was obtained, with tannic fractions presenting a higher contribution than anthocyanic fractions. These results not only confirmed that tannins have a major implication in red wine dryness but also unequivocally demonstrated a relevant implication of certain anthocyanins in this attribute. In contrast, bitterness of the original wines could not be directly related to the bitterness perceived in any of the two groups of fractions. The addition of an extremely bitter anthocyanic fraction to wines only increased bitterness in certain wines, suggesting that bitterness in wines may result from perceptual interactions and that some wines contain strong bitterness suppressors. [ABSTRACT FROM AUTHOR]

• Aroma does not have a main effect on taste or mouthfeel perception of red wines. • The only effect of aroma was observed for oily mouthfeel. • Oily mouthfeel was masked by earthy aromas and enhanced by alcoholic nuances. • Independent dimensions were related to dry/silky, grainy, prickly and oily. • Tannin concentration and activity and pH drove wine dryness. The present study was aimed at increasing the understanding of red wine mouthfeel by investigating the potential cross-modal effect of aroma and establishing relationships between sensory dimensions and chemical measurements. Investigations involved a set of 42 non-wooded red wines that were described with a novel application of a variant of the rate-all-that-apply sensory methodology ("rate- K attributes") by a group of Spanish wine experts under two conditions: (1) with no aroma perception (using nose clips) and (2) with aroma perception. In parallel, ethanol content, pH, titratable acidity, tannin activity, concentration of tannins, and spectroscopic measures of wines were determined. Results suggest that aroma does not play a main effect on taste or mouthfeel perception of red wines, except for oily mouthfeel, which was hypothesised to be masked by earthy aromas and enhanced by alcoholic nuances attributed to cognitive interactions. Independent and non-correlated mouthfeel dimensions such as dry/silky and sticky, grainy, prickly or oily were also identified. Tannin activity was shown to be highly positively correlated to dry on the palate, and tannin concentration with both overall dry and dry on the palate. A significant partial least squares regression model showed that tannin concentration and activity (positive contribution) as well as pH values (negative) were good predictors of the mouthfeel dimension mainly related to dry and sticky terms. [ABSTRACT FROM AUTHOR]

The present work seeks to define the “green character” of red wines and characterise the groups of molecules potentially involved in that perception. Fifty-four wines were screened by wine experts for different levels of green character. Six different phenolic fractions were obtained by liquid chromatography (LC) and further submitted to sensory and chemical characterisation. The volatile fraction was screened by semipreparative LC, Gas Chromatography-Olfactometry (GC-O) and quantitative analysis. The green character was linked to vegetal aroma, astringency, green and dry tannins according to experts of the Somontano region. Non-volatile fractions containing tannins with mean degree of polymerisation of ten and smaller anthocyanin-derivative pigments (

The absence of reference materials with defined mouthfeel properties makes it difficult to progress in finding the chemical compound or group of compounds responsible for such properties in complex foods or beverages such as wine. The present work aimed at developing a chemo-sensory strategy providing different odorless fractions with consistent mouthfeel properties. Three wines with different mouthfeel properties were separated in six different odorless fractions per wine by semipreparative liquid chromatography and Solid-Phase Extraction (SPE). Fractions were sensory analyzed by sorting task, repertory grid, triangulation and Rate-All-That-Apply (RATA) with wine experts. In parallel, fractions were chemically characterized by spectrophotometrical strategies, UPLC-MS and MALDI-TOF-MS. A list of 23 terms related to in-mouth properties (18 to mouthfeel) was generated and successfully employed in the description of wines and fractions by RATA analysis. Fractions containing oligomers of flavanols (from tetramers up to decamers) were mainly coarse , grainy , dry on the tongue and dry on the palate . More surprising was the sensory properties of a fraction containing anthocyanin-derivative pigments, which was especially dry , bitter and persistent as was the original wine. This fraction did not contain either oligomers or polymers of flavanols or flavanol-anthocyanin pigments, but a series of trimers of anthocyanins tentatively identified by MALDI-TOF MS. Further separation strategies are being developed to isolate anthocyanin-derived compounds to further confirm their sensory impact in wines. [ABSTRACT FROM AUTHOR]