terclim by ICS banner
IVES 9 IVES Conference Series 9 DOES LIGNIN AN ACCEPTABLE MARKER OF GRAPESEED MATURATION AND QUALITY?

DOES LIGNIN AN ACCEPTABLE MARKER OF GRAPESEED MATURATION AND QUALITY?

Abstract

Usually the winemaker consider polyphenols from the grape berry as an actor of the wine quality. There are frequently consider as a marker of grape maturity. It is commonly known that winemaker consider tannins and anthocyanins as main polyphenol actors for winemaking practices and wine quality. Here we will focus on the characterisation of lignins in grape seeds. Previous studies suggest that the seed is lignified [1], which could explain the change in colour of the seed when it reaches maturity and thus provide a reliable indicator for describing the maturity stage in the seed. Furthermore, lignin is contained in the outer envelope of the seeds [2] and would constitute a mesh that affects the extractability of tannins and therefore the quality of the wine obtained following the winemaking process [3], since these are mainly responsible for the astringency and bitterness in the wine. In order to provide initial answers on the establishment of lignin in the seed, as well as on the quantity and type of lignin found in the seed, a preliminary two-stage study was conducted.

In a first stage, the lignin biosynthesis pathway was studied using qPCR approach with a focus on key genes of the lignin pathway (PAL, 2 isoforms of COMT, CCOAMT, F5H and 2 isoforms of CAD). The analysis of level of transcripts show a differential regulation and timing of transcripts accumulation depending of the stage of maturity and the vintage studied.

In a second step, it was undertaken to identify and quantify the different lignin monomers present in the grapeseed. For this purpose, an extraction of lignins was carried out with an ethanol:toluene, ethanol, water sequence on seed powder. In order to determine the lignin content after extraction, an acetyl bromide procedure was performed as well as a thioacydolysis protocol to cleave the β-O-4 bonds of the lignin polymer and release the different lignin monomers G from guaiacyl, S from syringyl and H from p-hydroxyphenyl. Their identification and quantification was undertaken by HPLC-MS.

This first work on lignin determination in grapeseed give a solid baseline to go further in the comprehensive way to transfer of oenological molecules from grapeseed to must and wine almost in the context of climate change.

 

1. Cadot, Yves, et al. « Anatomical, Histological, and Histochemical Changes in Grape Seeds from Vitis Vinifera L. Cv Cabernet Franc during Fruit Development ». Journal of Agricultural and Food Chemistry, vol. 54, no 24, novembre 2006, p. 9206 15
2. Marles, MA Susan, et Margaret Y. Gruber. « Histochemical Characterisation of Unextractable Seed Coat Pigments and Quantification of Extractable Lignin in the Brassicaceae ». Journal of the Science of Food and Agriculture, vol. 84, no 3, février 2004, p. 251 62.
3. Lewis, Norman G. « A 20th Century Roller Coaster Ride: A Short Account of Lignification ». Current Opinion in Plant Biology, vol. 2, no 2, avril 1999, p. 153 62.

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Poster

Authors

Dorianne Ribet ¹, Clément Miramont ², Ghislaine Hilbert-Masson ³, Michael Jourdes¹, Amélie Rabot ¹*

1. University Bordeaux, Bordeaux INP, Bordeaux Sciences Agro, INRAE, UMR 1366, OENO, ISVV, F- 33140 Villenave d’Ornon, France
2. USC 1422 GRAPPE, INRAE, Ecole Supérieure d’Agricultures, SFR 4207, QUASAV, 55 rue Rabelais, 49100 Angers, France
3. UMR 1287, EGFV, Univ. Bordeaux, Bordeaux Sciences Agro, INRAE, ISVV, 33140 Villenave d’Ornon, France 

Contact the author*

Keywords

Grapeseed, maturation, biochemistry

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

IDENTIFICATION OF NEW RESVERATROL DERIVATIVES FORMED IN RED WINE AND THEIR BIOLOGICAL PROPERTIES

Stilbenes are natural bioactive polyphenols produced by grapevine. Recently, we have reviewed the na- tural presence of these compounds in wines [1]. This study showed that the resveratrol and its glycoside, the piceid, are the most abundant stilbenes in wines. Resveratrol is a well-known stilbene with a wide range of biological activities. Due to its specific structure, resveratrol can be oxidized in wines to form various derivatives including oligomers [2]. In this study, we investigate the resveratrol and piceid transformation in wines.

SENSORY DEFINITION OF A TECHNICAL UNAVOIDABLE TRANSFER OF AROMA COMPOUNDS VIA SEALING IN A BOTTLING LINE IN ORDER TO PREVENT PROSECUTION DUE TO FRAUDULENT AROMATIZATION OF A SUBSEQUENTLY FILLED WINE

In 2020, 12% of all bottled German wines were aromatized, which may increase further due to rising popularity of dealcoholized wines. As sealing polymers of a bottling line absorb aroma compounds and may release them into regular wines in the next filling¹, this unintentional carry-over bears the risk to violate the legal ban of any aromatization of regular wine. However, following EU legislation, German food control authorities accept a technical unavoidable transfer of aroma compounds, if this is of no sensory significance.

EFFECTIVENESS OF APPLIED MATERIALS IN REDUCING THE ABSORPTION OF SMOKE MARKER COMPOUNDS IN A SIMULATED WILDFIRE SCENARIO

Smoke taint (ST) is a grape-wine off-flavour that may occur when grapes absorb volatile phenols (VPs) originating from wildfire smoke (1). ST is associated with the negative sensory attributes such as smoky and ashy notes. VPs are glycosylated in the plant and thus present in both free and bound forms (2; 3). Wildfire smoke has resulted in a decline in grape and wine quality and financial losses which has become a prominent issue for the global wine industry.

PHOTOCHEMICAL DEGRADATION OF TRYPTOPHAN IN MODEL WINE: IMPACT OF HEAVY METALS AND OXYGEN ON 2-AMINOACETOPHENONE FORMATION

The wine industry worldwide faces more and more challenges due to climate change, such as increased dryness in some areas, water stress, sunburn and early harvesting during hot summer temperatures¹. One of the resulting problems for the wine quality might be a higher prevalence of the untypical aging off-flavor (ATA)². A substance, which Rapp and Versini made responsible for ATA, is the 2-aminoace-tophenone (2-AAP)³. 2-AAP in wine causes a naphthalene, wet towels, wet wool, acacia flower or just a soapy note⁴.

USE OF 13C CP/MAS NMR AND EPR SPECTROSCOPIC TECHNIQUES TO CHARACTERIZE MACROMOLECULAR CHANGES IN OAK WOOD(QUERCUS PETRAEA) DURING TOASTING

For coopers, toasting process is considered a crucial step in barrel production during which oak wood (Q. petraea) develops several aromatic nuances released to the wine during its maturation. Toasting consists of applying different degrees of heat to a barrel for a specific period. As the temperature increases, thermal degradation of oak wood structure produces a huge range of chemical compounds. Many studies have identified the main key aroma volatile compounds (whisky-lactone, furfural, eugenol, guaiacol, vanillin). However, detailed information on how the chemical structure of oak wood degrades with increasing toasting level is still lacking.