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…

FUNGAL DIVERSITY AND DYNAMICS IN CHAMPAGNE VINEYARDS: FROM VINE TO WINE

Champagne is a well-known wine region in Northern France with distinct terroirs and three main grape varieties. As for any vineyard, wine quality is highly linked to the microbiological characteristics of the raw materials. However, Champagne grape microbiota, especially its fungal component, has yet to be fully characterized. Our study focused on describing this mycobiota, from vine to small scale model wine, for the two main Champagne grape varieties, Pinot Noir and Meunier, using complementary cultural and omics approaches.

2-YEARS STUDY ON COMPARISON BETWEEN THE VOLATILE CHEMICAL PROFILE OF TWO DIFFERENT BLENDS FOR THE ENHANCEMENT OF “VALPOLICELLA SUPERIORE”

Valpolicella is a famous wine producing region in the province of Verona owing its fame above all to the production of two Protected Designation of Origins (PDOs) withered wines: Amarone and Recioto. In recent years, however, the wineries have been interested in the enhancement and qualitative increase of another PDO, Valpolicella Superiore. All the Valpolicella PDOs wines are produced with a unique grape blend, mainly Corvina, Corvinone, Rondinella and a range of other minor varieties.From 2019 Valpolicella product regulation has changed the grape proportion of the blend allowing new composition parameters of wines. For this reason, studying the volatile chemical profiles to support wine makers in the effort to produce high quality wines represents a field of great interest.

CONTRIBUTION OF VOLATILE THIOLS TO THE AROMA OF RIESLING WINES FROM THREE REGIONS IN GERMANY AND FRANCE (RHEINGAU, MOSEL, AND ALSACE)

Riesling wines are appreciated for their diverse aromas, ranging from the fruity fresh characters in young vintages to the fragrant empyreumatic notes developed with aging. Wine tasters often refer to Riesling wines as prime examples showcasing terroir, with their typical aroma profiles reflecting the geographical provenance of the wine. However, the molecular basis of the distinctive aromas of these varietal wines from major Riesling producing regions in Europe have not been fully elucidated. In this study, new lights were shed on the chemical characterization and the sensory contribution of volatile thiols to Riesling wines from Rheingau, Mosel, and Alsace. First, Riesling wines (n = 46) from the three regions were collected and assessed for their aroma typicality by an expert panel.

NEAR INFRARED SPECTROSCOPY FOR THE ESTIMATION OF TEMPRANILLO BLANCO VOLATILE COMPOSITION ALONG GRAPE MATURATION

Grape volatile compounds are mainly responsible for wine aroma, so it is important to know the va-rietal aromatic composition throughout ripening process. Currently, there are no tools that allow mea-suring the aromatic composition of grapes, in intact berries and periodically, throughout ripening, in the vineyard or in the winery. For this reason, this work evaluated the use of near infrared spectroscopy (NIR) to estimate the aromatic composition and total soluble solids (TSS) of Tempranillo Blanco berries during ripening. For this purpose, NIR spectra (1100-2100 nm) were acquired from 240 samples of in-tact berries, collected at different dates, from veraison to overripening.

NEW METHOD FOR THE QUANTIFICATION OF CONDENSED TANNINS AND OTHER WINE PHENOLIC COMPOUNDS USING THE AUTOMATED BIOSYSTEMS SPICA ANALIZER

Wine phenolic compounds are important secondary metabolites in enology due to their antioxidant and nutraceutical properties, and their role in the development of color, taste, and protection of wine from oxidation and spoilage. Tannins are valuable phenolic compounds that contribute significantly to these wine properties, especially in mouthfeel characteristics; however, tannin determination remains a significant challenge, with manual and time-consuming methods or complex methodologies. The purpose of this study is to propose a novel method for quantifying condensed tannins in finished wine products.