Macrowine 2021
IVES 9 IVES Conference Series 9 To a better understanding of the impact of vine nitrogen status on volatile thiols from plot to transcriptome level

To a better understanding of the impact of vine nitrogen status on volatile thiols from plot to transcriptome level

Abstract

Volatile thiols contribute largely to the organoleptic characteristics and typicity of Sauvignon blanc wines. Among this family of odorous compounds, 3-sulfanylhexan-1-ol (3SH) and 4-methyl-4-sulfanylpentan-2-one (4MSP) have a major impact on wine flavor. These thiols are formed during alcoholic fermentation by the yeast from odorless and non-volatile precursors found in the berry and the must. The effect of vine nitrogen status on 3SH and 4MSP in Sauvignon blanc wine and on the glutathionylated and cysteinylated precursors of 3SH (Glut-3SH and Cys-3SH) was investigated in this study. Moreover the impact of nitrogen fertilization on the expression of the glutathione-S-transferase 3 and 4 (VviGST3 and VviGST4) and the γ-glutamyltranspeptidase (VviGGT), considered as key genes in its genesis, was also evaluated. Nitrogen supply influenced positively the 3SH content in wine while no effect was noticed on 4MSP level. Furthermore, nitrogen increased Glut-3SH levels in grape berries mainly at mid-ripening and ripeness and in must at harvest. No significant effect of nitrogen addition was noticed on Cys-3SH concentration. The expression pattern of the three mentioned genes was similar between the control and the fertilized modality. New candidate genes which might be implicated in the biosynthetic pathway of 3SH precursors were identified by whole transcriptome shotgun sequencing (RNA-seq).

Publication date: May 17, 2024

Issue: Macrowine 2016

Type: Poster

Authors

Cécile Thibon*, Aude Habran, Cornelis van Leeuwen, Darriet Philippe, Eric Gomes, Ghislaine Hilbert, Pierre Helwi, Sabine Guillaumie, Serge Delrot

*ISVV-USC oeno

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Tags

IVES Conference Series | Macrowine | Macrowine 2016

Citation

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