IVAS 2022 banner
IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 Study of the evolution of tannins during wine aging by mass spectrometry monitoring of oxidation markers released after chemical depolymerization

Study of the evolution of tannins during wine aging by mass spectrometry monitoring of oxidation markers released after chemical depolymerization

Abstract

Among the many compounds in wine, condensed tannins play an important role in the organoleptic properties of the products; they are partly responsible for astringency, bitterness and also contribute to the color. This research work aims to study the oxidation state of these bio-heteropolymers which is an important lock in the analysis of processed products in order to better control their quality. Indeed, their identification remains at present a challenge because of the large heterogeneity of their degrees of polymerization (DP) based on 4 monomers (epicatechin, catechin, epigallocatechin, epicatechin-3-O-gallate) thus multiplying the number of oxidation products. Due to the difficulties of separation by liquid chromatography and detection by mass spectrometry of tannins with high DP1, tannins were analyzed by UHPLC-ESI-MS after chemical depolymerization. This pre-treatment of the samples allows the cleavage of the interflavanic bonds linking the constituent monomers of the tannins and gives access to the average DP and the proportions of the different monomers. However, in wines, many reactions take place from the beginning of the wine making process to its consumption. Within the tannin structures, the new covalent bonds created by oxidation are resistant to depolymerization conditions and oxidation markers (dimers and trimers) are then obtained. These structural modifications distort to a greater or lesser extent the estimation of the average DP depending on the oxidation state of the tannins. Faced with the complexity and the large number of oxidation products generated, over the last ten years a study conducted on model solutions has allowed the identification of more than one hundred oxidation markers2,3.
Thanks to the detection and identification of these oxidation markers, an in-depth study of the tannin fraction of wines has recently allowed us to understand theirs evolutions during ageing. Three Syrah wines (2018, 2014 and 2010 vintages) were analyzed. An accelerated oxidation of the 2018 vintage sample was also performed in order to evaluate the impact of this oxidation compared to the natural evolution and evaluate the ability of this oxidation to imitate natural evolution. The monitoring of 6 types of extension, extension/terminal and terminal markers at two oxidation levels was investigated. An evolution of the tannin oxidation state during ageing by the increase of the markers of the second oxidation level over the vintages was observed. In the 2018 oxidized wine sample, the first oxidation level markers are similar to the 2014 vintage but the second oxidation level markers are higher than other vintages, indicating a more advanced state of tannin oxidation. This study showed for the first time that it was possible to follow the oxidative evolution of wine tannins by monitoring some relevant dimeric tannin oxidation markers generated after chemical depolymerization.

DOI:

Publication date: June 27, 2022

Issue: IVAS 2022

Type: Poster

Authors

Mouls Laetitia1, Deshaies Stacy1, Garcia François1, Suc Lucas1 and Saucier Cédric1

1SPO, Univ Montpellier, INRAE, Institut Agro

Contact the author

Keywords

Proanthocyanidin, Flavan-3-ol, oxidation marker, wine aging

Tags

IVAS 2022 | IVES Conference Series

Citation

Related articles…

PERCEPTUAL INTERACTIONS PHENOMENA INVOLVING VARIOUS VOLATILE COMPOUND FAMILIES LINKED TO SOME FRUITY NOTES IN BORDEAUX RED WINES

Fruity notes play a key role in the consumer’s appreciation of Bordeaux red wines. If literature provides a lot of knowledge about the nature of volatile compounds involved in this fruity expression, the sensory phenomena involving these compounds in mixture still need to be explored. Considering previous sensory works about the impact of esters and some overripening compounds, the goal of this work was to study the implication of perceptual interactions involving red wine odorant compounds of diverse origins and described as potentially affecting fruity aromatic expression.
Read More

Parcours de découverte des terroirs viticoles

A partir des recherches conduites sur la caractérisation des terroirs viticoles par des chercheurs de l’Unité de Recherches Vigne et Vin (1, 2, 3, 4, 5) du Centre INRA d’Angers, Terre des Sciences, le Centre de Culture Scientifique et Technique d’Angers (CCSTA) a mis au point un parcours de découverte d’une journée dans le vignoble angevin avec une approche pluridisciplinaire.

Read More

Effect of moderate wine consumption in animal models

In 1979, the so-called “french paradox” was proposed, that is, a correlation between wine consumption, a diet rich in saturated fats, and a low mortality from coronary heart disease. On the other hand, it has also been described that alcohol consumption has negative effects on aging and increases the risk of liver cirrhosis and cancer. However, both hypotheses are based on population studies that may present distortions due to multiple factors (geographic, diet, smoking, socioeconomic level, etc.).

Read More

Grape seed flavanols extraction and mechanical-acoustic properties as influenced by maceration time and ethanol content

AIM: Grape flavanols are involved in wine quality markers such as in-mouth sensations and colour stability.

Read More

Characterizing the molecular basis of the differences in aromatic precursors found in commercial clones of Vitis vinifera cv. Tannat

Uruguay is known for the production of Tannat wines, which is a neutral variety from an aroma point of view, but capable of providing aromatic precursors that are of interest in the production of wines for ageing. The main aromatic precursors present are glycosidic compounds and carotenoids. The contribution of carotenoid degradation by-products such as norisoprenoids to wine aroma is fundamental, as they are associated with pleasant aroma descriptors and very low olfactory perception thresholds. Several factors have been shown to influence carotenoid concentrations in grapes, such as cultivar, climatic conditions, viticultural region, plant water status, exposure to sunlight and ripening stage.

Read More