terclim by ICS banner
IVES 9 IVES Conference Series 9 International Congress on Grapevine and Wine Sciences 9 2ICGWS-2023 9 Impact of toasting and botanical origin on oak wood (Q. sp.) volatilome using untargeted GCxGC-ToFMS analysis

Impact of toasting and botanical origin on oak wood (Q. sp.) volatilome using untargeted GCxGC-ToFMS analysis

Abstract

Many works have been carried out to identify the key aroma volatile compounds of oak wood (e.g., whisky-lactone, furfural, maltol, eugenol, guaiacol, vanillin) using conventional gas chromatography coupled with olfactometry and mass spectrometry (GC-O-MS). Inspired by recent untargeted approaches in the field of food “omics”, this work aims to extend our knowledge on the impact of cooperage process on the volatile composition of oak wood using two-dimensional comprehensive gas chromatography coupled with time of flight mass spectrometry (GCxGC-ToFMS).

In a first experiment, five levels of toasting intensity were selected and applied to Q. sessilis oak wood samples (control, 160 °C, 180 °C, 200 °C and 220 °C, 30 min, n=3). Organic extracts were prepared (CH2Cl2, 50 g/L) and analyzed by GCxGC-ToFMS on a combination of conventional nonpolar/midpolar columns (DB-5ms/Rxi-17Sil). Data processing was as follows: mass spectra (TIC) were deconvoluted (ChromaTOF software) and compared to spectra from a database for a tentative peak identification and some “filters” were applied to reduce the number of processed peaks. Using an R script, we identified 77 molecular markers associated with toasting intensity. Some of them were sensory active and well known in oak wood, such as guaiacol, creosol and isoeugenol, while others were identified for the first time, such as 2-methylbenzofuran (burnt), 3-methylcyclohexane-1,2-dione (coffee) and 2-hydroxy-2-cyclopenten-1-one (caramel). Their sensory impact was assessed by GC-MS and sensory analysis. Applying the same methodology through the previously developed R script, additional results were discussed on the ability of GCxGC-ToFMS to distinguish the botanical origins of oak wood (Q. sessilis, Q. robur, Q. alba).

DOI:

Publication date: October 5, 2023

Issue: ICGWS 2023

Type: Article

Authors

Marie Courregelongue1,2,3*, Warren Albertin1,2,4, Andrei Prida3, Alexandre Pons1,2,3

1Univ. Bordeaux, Bordeaux INP, INRAE, OENO, UMR 1366, ISVV, F-33140 Villenave d’Ornon, France
2Bordeaux Sciences Agro, Bordeaux INP, INRAE, OENO, UMR 1366, ISVV, F-33170 Gradignan, France

3Tonnellerie Seguin Moreau, Merpins, France
4ENSCBP, Bordeaux INP, 33600, Pessac, France

Contact the author*

Keywords

untargeted analysis, GCxGC-ToFMS, oak wood, thermal degradation, volatile compounds

Tags

2ICGWS | ICGWS | ICGWS 2023 | IVES Conference Series

Citation

Related articles…

Retrospective analysis of our knowledge regarding the genetics of relevant traits for rootstock breeding 

Rootstocks were the first sustainable and environmentally friendly strategy to cope with a major threat for Vitis vinifera cultivation. In addition to providing Phylloxera resistance, they play an important role in protecting against other soil-borne pests, such as nematodes, and in adapting V. vinifera to limiting abiotic conditions. Today viticulture has to adapt to ongoing climate change whilst simultaneously reducing its environmental impact. In this context, rootstocks are a central element in the development of agro-ecological practices that increase adaptive potential with low external inputs. Despite the apparent diversity of the Vitis genus, only few rootstock varieties are used worldwide and most of them have a very narrow genetic background. This means that there is considerable scope to breed new, improved rootstocks to adapt viticulture for the future.

Polyphenol content of cork granulates at different steps of the manufacturing process of microagglomerated stoppers treated with supercritical CO2 used for wine bottling

The wine closure industry is mainly divided into three categories: screw caps, synthetic closures, and cork-based closures. Among this latter, microagglomerated cork stoppers treated with supercritical CO2 are now widely used, especially to avoid cork taint contaminations[1]. They are designed with cork granules obtained from cork offcuts of the punching process during the natural cork stoppers production. A previous study[2] showed that these stoppers released fewer polyphenols in 12 % (v/v) hydroalcoholic solution than natural cork stoppers.

Evaluation of terroir suitability for vine cultivation in new areas using geographic multi-criteria decision support

Based on historical vine cultivation, the recent development of wine production in Drama wine region (Greece) has led to vine cultivation expansion of white and red varieties. The current cultivation of 500 ha of vineyards is expected to increase in the coming years. Natural terroir units (NTU) have been designed recently to support the production of high quality wines in the region [1]. The aim of this work is to evaluate the relevancy of the proposed NTUs regarding their suitability to produce wines of specific sensorial identity, and to provide guidelines for correct site selection for the expanding wine industry of the region.

New tool to evaluate color modifications during oxygen consumption in white and red wines

Measuring the effect of oxygen consumption on the color of wines as the level of dissolved oxygen decreases over time is very useful to know how much oxygen a wine can consume without significantly altering its color. The changes produced in wine after being exposed to high oxygen concentrations have been studied by different authors, but in all cases the wine has been analyzed 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[1,2].

Investigation of cellulose nanofiber-based films used as a protective layer to reduce absorption of smoke phenols into wine grapes

Volatile phenols from wildfire smoke are absorbed by wine grapes, resulting in undesirable smoky and ashy sensory attributes in the affected wine.[1] Unfortunately the severity of wildfires is increasing, particularly when grapes are ripening on the vine. The unwanted flavors of the wine prompted a need for solutions to prevent the uptake of smoke compounds into wine grapes. Films using cellulose nanofibers as the coating forming matrix were developed as an innovative means to prevent smoke phenols from entering Pinot noir grapes. Different film formulations were tested by incorporating low methoxy pectin or chitosan.