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…

Effects of environmental factors and vineyard pratices on wine flora dynamics

he intensification of t vineyard practices led to an impoverishment of the biological diversity. In vineyard management, the reflection to reduce pesticides uses concerns mainly the soil management of the vineyard, and often focuses on flora management in the inter-row.

Protein extracts of the Andean pseudocereals quinoa and kiwicha as alternatives for the fining of wine phenolics.

INTRODUCTION: Lately, there has been an increasing interest in using plant-derived proteins for wine phenolic fining.

REVINE project : regenerative agricultural approaches to improve ecosystem services in Mediterranean vineyards

REVINE is a 3 year European projected funded by PRIMA programme which proposes the adoption of regenerative agriculture practices with an innovative and original perspective, in order to improve the resilience of vineyards to climate change in the Mediterranean area.
Regenerative agriculture ameliorates soil structure and microbial biodiversity that, in turn, leads to crop resilience against biotic and abiotic stressful factors. Moreover, enrichment of beneficial microbes in the rhizosphere, such as PGPR and PGPF, are known to trigger the plant immunity inducing the priming state.

Il Lambrusco reggiano e il territorio di pianura: un modello efficace

Il caso “Lambrusco” è emblematico di un buon connubio tra un gruppo di vitigni ed un territorio di pianura caratterizzato da suoli fertili e alluvionali, che determinano un elevato sviluppo

Exploring the gene regulatory networks of WRKY family in grapevine (Vitis vinifera  L.) using DAP-Seq

The recent development of regulatory genomics has raised increasing interest in plant research since transcriptional regulation of genes plays a pivotal role in many biological processes. By shedding light on the target genes of the various transcription factors (TFs), it is therefore possible to infer the influence they exert on the different molecular mechanisms. In this regard, the attention was focused on WRKYs, a family of TFs almost exclusively found in plant species. In grapevine, WRKYs are involved in several biological processes, playing a key role in berry development, hormonal balance and signalling, biotic and abiotic stresses responses, and secondary metabolites biosynthesis.