Aug 20, 2024
Quantification of varietal aroma compounds, oak markers, and Strecker aldehydes in wines by SPE and gas chromatography–tandem mass spectrometrytry
- Cécile Thibon1,
- Emilie Suhas1,2,
- Alexandre Pons1,3
- 1Univ. Bordeaux, Bordeaux INP, INRAE, UMR 1366 OENO, ISVV, F-33140 Villenave d’Ornon, France;
- 2Diam Bouchage, Céret, 66400, France;
- 3Tonnellerie Seguin Moreau, Cognac, 16103, France
Protocol Citation: Cécile Thibon, Emilie Suhas, Alexandre Pons 2024. Quantification of varietal aroma compounds, oak markers, and Strecker aldehydes in wines by SPE and gas chromatography–tandem mass spectrometrytry. protocols.io https://dx.doi.org/10.17504/protocols.io.dm6gpzd18lzp/v1
License: This is an open access protocol distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Protocol status: Working
We use this protocol and it's working
Created: June 25, 2024
Last Modified: August 20, 2024
Protocol Integer ID: 102361
Keywords: wine, GC-MS/MS, SPE, varietal aroma, oak aroma, Strecker aldehydes
Abstract
This protocol outlines the conditions for the assaying volatile impact compounds in white and red wines by gas chromatography–tandem mass spectrometry (GC–MS/MS). This method enables the quantification of volatile thiols (3SH: 3-sulfanylhexanol; 3SHA: 3-sulfanylhexyl acetate; 4MSP: 4-methyl-4-sulfanylpentan-2-one; BM: benzenemethanethiol; E2SA: ethyl 2-sulfanylacetate; and FFT: furfurylthiol), odoriferous oxidation markers (methional, ortho-acetominophenone, and phenylacetaldehyde) in dry white wines, the main furanones and lactones associated with jammy fruit notes in red wines, terpenes (linalool, α-terpineol, nerol, geraniol), C13-norisoprenoids (β-damascenone and β-ionone), and oak wood markers (vanillin, eugenol, whisky lactone, guaiacol, nerol). This method represents an optimization and automation of the one described by Thibon et al (2015).
Materials
Gilson GX-274 ASPEC solid-phase extraction system (Villiers-Le-Bel, France)
HR-X CHROMABOND (500 mg, 6mL, Nacherey-Nagel, France)
Trace GC Ultra gas chromatograph coupled to a TSQ Quantum XLS triple quadrupole mass spectrometer (Thermo Electron SAS, Courtaboeuf, France)
OPTIMA WAX, 100% Polyethylene glycol, 60 m; 0.25 mm; 0.25 µm (Macherey-Nagel, Germany)
Extraction of volatile compounds
Extraction of volatile compounds
The SPE procedure was automated with a Gilson GX-274 ASPEC solid-phase extraction system (Villiers-Le-Bel, France). HR-X CHROMABOND (500 mg, 6mL, Nacherey-Nagel, France) was first activated with methanol (7 mL, 6 mL/min), washed twice with ultrapure water/ethanol (90/10, v/v; 2 mL, 5 mL/min). 20 mL of wine spiked with 50 µL an internal standard mix (6-sulfanylhexanol (1.5 mg/L), 4-methoxy-2-methyl-2-sulfanylbutan (1.5 mg/L), 3-octanol (1 mg/L), and EDTA (12 mg/L)) were then loaded onto the SPE cartridge at 3 mL/min. The cartridge was rinsed with water (2 mL, 5 mL/min), dried by air push (8 mL, 6 mL/min), and then the analytes were recovered by passing 3 mL of a solvent mixture of pentane/dichloromethane (50/50, v/v, 2 mL/min) and 3 mL of dichloromethane/methanol (95/5, v/v, 2 mL/min). The final organic phase was dried with anhydrous sodium sulfate and concentrated to 150 µL under a nitrogen stream.
GC-MS/MS analysis
GC-MS/MS analysis
Samples were analyzed using a chromatographic system comprising a Trace GC Ultra gas chromatograph (Thermo Electron SAS, Courtaboeuf, France) coupled to a TSQ Quantum XLS triple quadrupole mass spectrometer. GC separation was carried out on a polar wax capillary column (OPTIMA WAX, 100% Polyethylene glycol, 60 m; 0.25 mm; 0.25 µm) from Macherey Nagel (Germany). The carrier gas was helium (Messer, France), 6.0 grade, with a flow rate of 1 mL/min. A 1µL sample was injected via the autosampler (Triplus RSH autosampler, Thermo Electron SAS) into a split/splitless programmable-temperature injector (splitless time: 1 min, split flow 20 mL/min) set as follows: 0.05 min at 180°C, then raised to 230°C at 14°C/min, maintained for 1 min, and then raised to 250°C at 14°C/min and kept at that temperature for 10 min. Oven temperature was initially set at 45◦C, held for 1
min, then raised to 230°C at 4°C/min, raised to 250°C at 20°C/min, and finally held at this temperature for 10 min. The MS transfer line temperature was set at 260°C.
The source parameters including source temperature, electron energy, and emission current were set at 230°C, 70 eV, 50 µA and 100 V respectively. The collision gas was argon and the mass spectrometer was operated in electron impact (EI) mode. The SRM conditions were optimised for each compound in terms of collision energy and gas pressure values applied to each precursor ion depending on the transition. Precursor ion (m/z), product ion (m/z) and collision energy (V) selected as follows for compounds were indicated in table. Instrument set-up, data acquisition, and processing were performed using Xcalibur software (version 2.1.0). PFTBA (perfluorotributylamine) was used for mass calibration.
Retention time (RT), precursor ion (m/z), product ion (m/z) and collision energy (V) selected for each compound.
Protocol references
Bruez É., Cholet C., Thibon C., Redon P., Lacampagne S., Martignon T., Guidicci M., Darriet P., Gény L., 2021. Influence of curettage on Esca-diseased Vitis vinifera L. cv. Sauvignon blanc plants on the
quality of musts and wines. OENO One, 55 (1), 171-182.
Pons A., Lavigne V., Suhas E., Thibon C., Redon P., Loisel C., Darriet P., 2022. 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. Journal of Agricultural and Food Chemistry, 70 (51), 16358-16368.
Thibon C., Pons A., Mouakka N., Redon P., Méreau R., Darriet P., 2015. Comparison of electron and chemical ionization modes for the quantification of thiols and oxidative compounds in white wines by gas chromatography-tandem mass spectrometry. Journal of Chromatography A, 1415, 123-133.