Macrowine 2021
IVES 9 IVES Conference Series 9 Understanding sweetness of dry wines: first evidence of astilbin isomers in red wines and quantitation in a one-century range of vintages

Understanding sweetness of dry wines: first evidence of astilbin isomers in red wines and quantitation in a one-century range of vintages

Abstract

The gustatory balance of wines relies on sweetness, bitterness and sourness. In dry wines, sweetness does not result from the presence of residual sugar as in sweet wines, but is due to other non-volatile compounds. Such taste-active compounds are released during winemaking, by grapes, yeasts or oak wood and belong numerous chemical families [1]. Beyond this diversity, stereochemistry of molecules can also influence their sensory properties [2]. However, the molecular determinants associated with this taste have only been partially elucidated. Astilbin (2R, 3R) was recently reported to contribute to wine sweetness [3]. As its aglycon contains two stereogenic centers, three other stereoisomers may be present: neoisoastilbin (2S, 3R), isoastilbin (2R, 3S), and neoastilbin (2S, 3S). These compounds have already been observed in natural products, but never in wine. This work aimed at assaying their presence for the first time in wines as well as their taste properties.The isomers were synthesized from astilbin and purified by semi-preparative HPLC. Their content was assayed by developing a UHPLC-Q-Exactive quantification method. The method was applied to screen astilbin and isomers in various wines, especially in different vintages from the same estate. Sensory analysis highlighted the sweet taste of these stereoisomers whose intensity varied according to their configuration. Quantification results revealed that while young wines contained higher concentrations of astilbin than the old ones, the concentrations of the other isomers, mainly neoastilbin, were higher in the old wines, suggesting their formation over time.These results highlight the contribution of astilbin isomers in wine sweetness. More generally, this study brings new insights to understand the chemical origin of wine taste.

DOI:

Publication date: September 17, 2021

Issue: Macrowine 2021

Type: Article

Authors

Marie Le Scanff , Syntia FAYAD, Axel MARCHAL, 

Unité de recherche Œnologie, EA 4577, USC 1366 INRA, ISVV, Université de Bordeaux, F33882 Villenave d’Ornon, France 

Contact the author

Keywords

sweetness, sensory analysis, taste, isomers, wines

Citation

Related articles…

The influence of native flora on Argentine white terroir cv. Torrontes Riojano

The main objective of this paper is to establish considerable differences between wines from three wine areas or terroir, made with cv Torrontes Riojano.

Read More

Advancement of grape maturity – comparison between contrasting varieties and regions

Grapevine phenology has advanced across many regions, nationally and internationally, in recent decades under the influence of increasing temperatures, resulting in earlier
vintages (Jones and Davis, 2000, Petrie and Sadras, 2008, Tomasi et al., 2011, Webb et al., 2011. Earlier vintages have several ramifications for the wine industry. There are direct implications on quality, due to the fruit ripening during the hotter conditions of summer and early autumn, which then impacts grape composition and wine style (Sadras et al., 2013, Buttrose et al., 1971, Mira de Ordũna, 2010). There are also indirect implications where the fruit is perceived to ripen at a faster rate and the crop reach optimum maturity over a shorter period (Coulter et al., 2016).

Read More

Metschnikowia pulcherrima: A valuable microbial bioresource from wine for smart agrifood

The yeast Metschnikowia pulcherrima is a microorganism of great biotechnological interest, both for improving winemaking processes and for other applications outside the wine supply chain.

Read More

Methyljasmonate versus nanomethyljasmonate: effect on monastrell nitrogen composition

The aim of this work was to evaluate the effect of preharvest application in Monastrell berries using two different types of applications: conventional treatments

Read More

Exploring high throughput secondary trait phenomics to improve grapevine breeding

Modern grapevine breeding programs have overcome many challenges using genomic selection, which has allowed breeders to make targeted selections at earlier stages in the breeding process. However, the cost of genetic testing may present a burden for some programs, and markers often struggle to accurately predict quantitative traits. Recent advances in high throughput, high-dimensional data have provoked investigation into the use of high-dimensional phenomics as a low-cost addition to the grape breeder’s toolkit that may offer advantages in predicting quantitative traits. High-dimensional secondary trait (HDST) data has been employed in annual crops for prediction of agriculturally important traits such as yield.

Read More