Sensory-active compounds influencing wine experts' and consumers' perception of red wine
For experts, wine quality is linked to high contents of norisoprenoids. For consumers, wine quality is linked to high contents of oak-related volatiles. Ethanol increases finish intensity and duration of coconut and floral flavors in red wine
There is a lack of studies focusing on the chemical compounds involved in quality perception.
A Washington State work combines both sensory and chemical approaches with the final goal of evaluating the sensory-active compounds influencing wine experts' and consumers' perception of red wine quality.
Perceived quality was categorised by 108 consumers and 119 experts according to four levels going from very low to very high quality. In parallel, samples were described by a descriptive trained panel and volatile and non-volatile chemicals with known sensory activity were quantified.
Wines with higher concentrations of eugenol, E− and Z-whiskylactones and 4-ethylphenol (discussed in terms of matrix effect) are perceived higher in quality by consumers, while fusel alcohols and astringent-related compounds such as PAs, cis-aconitic acid, certain flavonols and hydroxycinnamic acid derivatives are linked to lower quality samples. In contrast, experts perceived wines with lower levels of whiskylactones and volatile phenols while higher levels of norisoprenoids to be higher in quality.
Wine finish, the tastes and aromas that linger after swallowing wine, is a critical aspect of wine quality. The objective of this study was to use time-intensity (TI) methodology to determine whether the finish parameters of different flavors varied as a function of wine matrix composition.
Trained panelists (n = 10) executed TI evaluations on three flavor compounds (2-phenylethanol (floral), 3-isobutyl-2-methoxypyrazine (bell pepper), and oak lactone (coconut)), heat, and astringency in wine adjusted to varying ethanol and tannin levels.
Multivariate analysis of variance indicated that elevated ethanol increased duration and intensity of the finish for floral and coconut samples (p < 0.05). For floral and bell pepper, no significant differences were shown using canonical variates analysis (CVA); however, for coconut, the high ethanol samples were more associated with a higher finish intensity and longer duration of finish.
Flavor interactions also affected finish duration, with coconut (oak lactone) finish duration shortened by 10.35 s in the presence of 2-phenylethanol.
These results showed that the wine matrix affects red wine finish and can be used by winemakers to understand how different processing techniques that alter the ethanol and tannin content of their wines, may also be affecting the sensory qualities of the wine finish.
Allison K. Baker, Carolyn F. Ross, Wine finish in red wine: The effect of ethanol and tannin concentration, Food Quality and Preference, Volume 38, December 2014, Pages 65-74, ISSN 0950-3293
María-Pilar Sáenz-Navajas, José-Miguel Avizcuri, Jordi Ballester, Purificación Fernández-Zurbano, Vicente Ferreira, Dominique Peyron, Dominique Valentin, Sensory-active compounds influencing wine experts' and consumers' perception of red wine intrinsic quality, LWT - Food Science and Technology, Volume 60, Issue 1, January 2015, Pages 400-411, ISSN 0023-6438