terclim by ICS banner
IVES 9 IVES Conference Series 9 CONTRIBUTION OF VOLATILE THIOLS TO THE AROMA OF RIESLING WINES FROM THREE REGIONS IN GERMANY AND FRANCE (RHEINGAU, MOSEL, AND ALSACE)

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

Abstract

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. Based on sensory assessment, selected wines were examined for their global aroma profile by sensory guided odorant screening techniques (preparative high pressure liquid chromatography; gas chromatography–mass spectrometry/olfactometry (GC–MS/O); sensory evaluation), and several odorous zones (OZs) of interest resembling the original olfactory notes (citrus, tropical fruits etc.) of the initial wines were noted. The aroma descriptors, linear retention index, and mass spectra of the suspected chromatography peaks and their accompanying OZs of interest revealed the presence and importance of volatile thiols in Riesling wines analysed. Hence, selective silver ion solid phase extraction and multidimensional GC–MS/O were applied for further characterization of targeted thiol-relevant OZs, allowing tentative identification of unknown thiols, with one new mercapto monoterpenoid confirmed by orthogonal approach. Following the sensory guided qualitative screening efforts, a new and highly sensitive quantitation method based on chemical derivatization and liquid chromatography quadrupole Orbitrap high-resolution MS was developed for the analysis of a substantial number of known and newly identified volatile thiols in the wine set. Quantitative results confirmed the relevance of 13 odorous thiols in Riesling, with several of them presented at concentrations well over their perception thresholds, as 3-sulfanylhexanol for instance. Thus, the combination of the chemical analysis of thiols and the sensory evaluation made it possible to draw up regional profiles according to the origin of the wines.

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Article

Authors

Emilio De Longhi1,2,3, Liang Chen1, 2, †, Pascaline Redon1, 2, Christoph Schüssler4, Rainer Jung4, Claus Patz5, Doris Rau-Hut3, Philippe Darriet1,2

1. Université de Bordeaux, Bordeaux INP, INRAE, OENO, UMR 1366, ISVV, F-33140 Villenave d’Ornon, France
2. Bordeaux Sciences Agro, Bordeaux INP, INRAE, OENO, UMR 1366, ISVV, F-33170 Gradignan, France
3. Hochschule Geisenheim University, Department of Microbiology and Biochemistry, Von-Lade-Str. 1, 65366 Geisenheim, Germany
4. Hochschule Geisenheim University, Department of Enology, Von-Lade-Str. 1, 65366 Geisenheim, Germany
5. Hochschule Geisenheim University, Department of Beverage Research, Von-Lade-Str. 1, 65366 Geisenheim, Germany †Current address: E. & J. Gallo Winery, 600 Yosemite Boulevard, Modesto, CA 95354, United States

Contact the author*

Keywords

Riesling wine aroma, Volatile thiols, Identification, Quantitation

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

HYDROXYTYROSOL PRODUCTION BY DIFFERENT YEAST STRAINS: SACCHAROMYCES AND NON-SACCHAROMYCES AND THE RELATION WITH THE NITROGEN CONSUMPTION

Hydroxytyrosol (HT) is a phenolic compound with extensive bioactive properties. It is present in olives, olive oil and wines. Its occurrence in wines is partly due to yeast synthetise tyrosol from tyrosine by the Ehrlich pathway, which is subsequently hydroxylated to .
The aim of the present work is to study how different yeast strains can influence in the HT production and, how the different nitrogen consumption of each strain can interfere the production of bioactive compounds.

Microbial ecosystems in wineries – molecular interactions between species and modelling of population dynamics

Microbial ecosystems are primary drivers of viticultural, oenological and other cellar-related processes
such as wastewater treatment. Metagenomic datasets have broadly mapped the vast microbial species
diversity of many of the relevant ecological niches within the broader wine environment, from vineyard
soils to plants and grapes to fermentation. The data highlight that species identities and diversity
significantly impact agronomic performance of vineyards as well as wine quality, but the complexity
of these systems and of microbial growth dynamics has defeated attempts to offer actionable
tools to guide or predict specific outcomes of ecosystem-based interventions.

MONOSACCHARIDE COMPOSITION AND POLYSACCHARIDE FAMILIES OF LYOPHILISED EXTRACTS OBTAINED FROM POMACES OF DIFFERENT WHITE GRAPE VARIETIES

The recovery of bioactive compounds from grape and wine by-products is currently an important and necessary objective for sustainability. Grape pomace is one of the main by-products and is a rich source of some bioactive compounds such as polyphenols, polysaccharides, fatty acids, minerals and seed oil. Polysaccharides contained in the grape cell wall can be rhamnogalacturonans type II (RG-II), polysaccharides rich in arabinose and galactose (PRAG), mannoproteins (MP), homogalacturonans (HG) and non pectic polysaccharides (NPP).

WHICH IMPACT FOR PROANTHOCYANIDIC TANNINS ON RED WINE FRUITY AROMA? SENSORY AND PHYSICOCHEMICAL APPROACHES

Previous research on the fruity character of red wines highlighted the role of esters. Literature provides evidence that, besides these esters, other compounds that are not necessarily volatiles may have an important impact on the overall aroma of wine, contributing to a modulation of its global aromatic expression. The goal of this work was to assess the olfactory consequences of a mixture between esters and proanthocyanidic tannins, through sensory and physico-chemical approaches.
Sensory analysis of numerous aromatic reconstitutions, including triangular tests, detection thresholds, and sensory profiles, were conducted in order to evaluate the sensory impact of tannins on red wine esters perception.

EVALUATION OF A SEAWEED EXTRACT OF RUGULOPTERYX OKAMURAE AGAINST ERYSIPHE NECATOR IN GRAPEVINE

Powdery mildew, caused by Erysiphe necator, is a widespread disease that causes high economical losses in viticulture. The main strategy to control the disease is the recurrent application of sulphur based phytochemical compounds. However, in order to reduce their accumulation in the environment and promote the sustainability of the sector, the European Commission has applied restrictions to the number of pesticide treatments and the maximum quantity of fungicides to be applied in viticulture. Seaweeds, in particular macroalgae, are marine resources rich in sulphated polysaccharides with bio-protective potential for the plant, representing an environmentally-friendly alternative approach for sustainable wine production.