terclim by ICS banner
IVES 9 IVES Conference Series 9 OPTIMIZING THE IDENTIFICATION OF NEW THIOLS AT TRACE LEVEL IN AGED RED WINES USING NEW OAK WOOD FUNCTIONALISATION STRATEGY

OPTIMIZING THE IDENTIFICATION OF NEW THIOLS AT TRACE LEVEL IN AGED RED WINES USING NEW OAK WOOD FUNCTIONALISATION STRATEGY

Abstract

During bottle aging, many thiol compounds are involved in the expression of bouquet of great aged red wines according to the quality of the closure.1,2 Identifying thiol compounds in red wines is a challenging task due several drawbacks including, the complexity of the matrix, the low concentration of these impact compounds and the amount of wine needed.3,4

This work aims to develop a new strategy based on the functionalisation of oak wood organic extracts with H₂S, to produce new thiols, in order to mimic what can happen in red wine during bottle aging. Following this approach and through sensory analysis experiments, we demonstrated that the vanilla-like aroma of fresh oak wood was transformed into intense “meaty” nuances similar to those found in old but non oxidized red wines.5 Functionalized samples were analysed by gas chromatography coupled with a pulsed flame photometric detector (GC-PFPD) and olfactometry (GC-O) to optimize the reaction conditions. Analysis of functionalized oak wood organic extracts by GC-O and GC-PFPD led us to detect six OZ reminiscent of “meaty” nuances and associated with sulphur compounds. One of them was characterized by preparative multi-dimensional gas chromatography coupled with olfactometry and time of flight mass spectrometry (Prep-MDGC-O-TOF MS) and identified as 2-methoxybenzenethiol.

This thiol was also identified in red wines following extraction by SPE, separation and detection by means of GC-MS/MS (SRM mode). The validation of the quantification method was carried out before its use to study its distribution in wines, young and old from different appellations and according to the OTR (determined by coulometry) of the closure. We show that its concentration can reach the odour detection threshold determined at 607 ng/L. Following the same strategy, five other thiols reminiscent of “meaty” nuances, including 2,5-dimethylfuran-3-thiol, 5-methyl-2-furfurylthiol, o-toluenethiol, 2,6-dimethylbenzenethiol and 2,6-dimethoxybenzenethiol were also identified for the first time in red wines. Their sensory impact will also be discussed.

 

1. Picard, M.; Thibon, C.; Redon, P.; Darriet, P.; de Revel, G.; Marchand, S. Involvement of Dimethyl Sulfide and Several Polyfunctional Thiols in the Aromatic Expression of the Aging Bouquet of Red Bordeaux Wines. J. Agric. Food Chem. 2015, 63 (40), 8879–8889. https://doi.org/10.1021/acs.jafc.5b03977.
2. Pons, A.; Lavigne, V.; Suhas, E.; Thibon, C.; Redon, P.; Loisel, C.; Darriet, P. Impact of the Closure Oxygen Transfer Rate on Volatile Compound Composition and Oxidation Aroma Intensity of Merlot and Cabernet Sauvignon Blend: A 10 Year Study. J. Agric. Food Chem. 2022, 70 (51), 16358–16368. https://doi.org/10.1021/acs.jafc.2c07475.
3. Pons, A.; Lavigne, V.; Eric, F.; Darriet, P.; Dubourdieu, D. Identification of Volatile Compounds Responsible for Prune Aroma in Prematurely Aged Red Wines. J. Agric. Food Chem. 2008, 56 (13), 5285–5290. https://doi.org/10.1021/jf073513z.
4. Chen, L.; Darriet, P. Strategies for the Identification and Sensory Evaluation of Volatile Constituents in Wine. Compr. Rev. Food Sci. Food Saf. 2021, 20 (5), 4549–4583. https://doi.org/10.1111/1541-4337.12810.
5. Picard, M.; Tempere, S.; de Revel, G.; Marchand, S. A Sensory Study of the Ageing Bouquet of Red Bordeaux Wines: A Three-Step Approach for Exploring a Complex Olfactory Concept. Food Qual. Prefer. 2015, 42, 110–122. https://doi.org/10.1016/j. foodqual.2015.01.014.

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Article

Authors

Emilie Suhas1,2,4, Svitlana Shinkaruk1,2, Alexandre Pons1,2,3

1. Univ. 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. Seguin Moreau France, Z.I. Merpins, BP 94, 16103 Cognac, France
4. Diam bouchage, Céret 66400, France

Contact the author*

Keywords

Red wines, Thiol compounds, Meaty aroma, Oak wood functionalisation strategy

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

ACIDIC AND DEMALIC SACCHAROMYCES CEREVISIAE STRAINS FOR MANAGING PROBLEMS OF ACIDITY DURING THE ALCOHOLIC FERMENTATION

In a recent study several genes controlling the acidification properties of the wine yeast Saccharomyces cerevisiae have been identified by a QTL approach [1]. Many of these genes showed allelic variations that affect the metabolism of malic acid and the pH homeostasis during the alcoholic fermentation. Such alleles have been used for driving genetic selection of new S. cerevisiae starters that may conversely acidify or deacidify the wine by producing or consuming large amount of malic acid [2]. This particular feature drastically modulates the final pH of wine with difference of 0.5 units between the two groups.

ASSESSING THE ROLE OF 27 KNOWN BITTER COMPOUNDS IN COMMERCIAL WHITE WINES COMBINING LC-MS QUANTIFICATION AND SENSORY ANALYSIS

The balance between the different flavours of a wine largely determines its perception and appreciation by the consumers. In white wines, sweetness and sourness are usually the two poles balancing the taste properties. The bitter flavour, on the other hand, is frequently associated with a loss of equilibrium and all white wines (dry and sweet, young and aged) are affected.
Several bitter compounds are already well-described in wines.

MICROFLUIDIC PLATFORM FOR SORTING YEAST CELLS ACCORDING TO THEIR MORPHOLOGY

In this work we briefly present a microfluidic device aiming to sort yeast cells according to their morphology. The technology is based upon microfluidic chips made out of Polydimethylsiloxane and glass using soft lithography processes and replica molding. The microfluidic device was used for encapsulating single yeast cells in liquid droplets containing growth medium. Liquid droplet containing yeast cells were sorted using a real time imaging and decision-making process.

NEW INSIGHTS INTO THE FATE OF MARKERS INVOLVED IN FRESH MUSHROOM OFF-FLAVOURS DURING ALCOHOLIC FERMENTATION

The fresh mushroom off-flavour (FMOff) has been appearing in wines since the 2000s. Some C8 compounds such as 1-octen-3-one, 1-octen-3-ol, 1-hydroxyoctan-3-one, 3-octanol and others are involved in this specific off-flavour [1-3]. At the same time, glycosidic precursors of some FMOff compounds have been identified in musts contaminated by Crustomyces subabruptus [4], highlighting the role of aroma precursors in this specific taint. However, the fate of these volatile molecules and glycosidic fractions during fermentation is not well known.

NEW TOOL FOR SIMULTANEOUS MEASUREMENT OF OXYGEN CONSUMPTION AND COLOUR MODIFICATIONS IN WINES

Measuring the effect of oxygen consumption on the colour of wines as the level of dissolved oxygen decreases over time is very useful to know how much oxygen a wine is able to consume without significantly altering its colour. The changes produced in wine after being exposed to high oxygen concen-trations have been studied by different authors, but in all cases the wine has been analysed once the oxygen consumption process has been completed. This work presents the results obtained with the use of an equipment designed and made to measure simultaneously the level of dissolved oxygen and the spectrum of the wine, during the oxygen consumption process from saturation levels with air to very low levels, which indicate the total consumption of the dosed oxygen.