Investigation of Thiol Levels in Young Commercial South African Sauvignon Blanc and Chenin Blanc Wines Using Propiolate Derivatization and GC-MS/MS
Abstract
In this work, the ethyl propiolate method for analysing thiols in white wine by GC-MS, originally proposed by Herbst-Johnstone et al.) (2013), has been adapted to GC-MS/MS and has been validated. The method performance has shown improvement in terms of sensitivity (limit of detection, LOD) and of the number of compounds measured. In addition to 3-mercaptohexanol (3MH), 3-mercaptohexyl acetate (3MHA), and 4-mercapto-4-methylpentan-2-one (4MMP), the adapted method can also measure 2-furanmethanethiol (FMT) and makes use of a commercially-available internal standard (IS), 4-methoxy-2-methyl-2-butanethiol (4M2M2B, IS). The proposed method was applied to determine thiol levels in young commercial South African Sauvignon and Chenin Blanc wines. The samples (n=20 for each cultivar) were chosen according to a high frequency of the typical descriptors associated with this class of impact compounds. 3MH was found at 178-904 ng/L and 99-1124 ng/L, and 3MHA at 23-151 ng/L and 5-253 ng/L in Sauvignon and Chenin Blanc respectively. 4MMP was present in Sauvignon Blanc in concentrations up to 21.9 ng/L, but in none of the Chenin Blanc samples.
Downloads
References
Capone, D.L., Ristic, R., Pardon, K.H. & Jeffrey, D.W., 2015. Simple quantitative determination of potent thiols at ultratrace levels in wine by derivatization and high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) analysis. Analytical Chemistry 87(2), 1226–1231.
Coetzee, C. & du Toit, W.J., 2012. A comprehensive review on Sauvignon blanc aroma with a focus on certain positive volatile thiols. Food Research International 45(1), 287–298.
Danilewicz, J.C., Seccombe, J.T. & Whelan, J., 2008. Mechanism of interaction of polyphenols, oxygen, and sulfur dioxide in model wine and wine. American Journal of Enology and Viticulture 59(2), 128–136.
Herbst-Johnstone, Piano, F., Duhamel, N., Barker, D. & Fedrizzi, B., 2013. Ethyl propiolate derivatisation for the analysis of varietal thiols in wine. Journal of Chromatography A, 1312, pp.104–110.
Musumeci, L.E., Ryona, I., Pan, B.S., Loscos, N., Feng, H., Cleary, M.T. & Sacks, G.L., 2015. Quantification of polyfunctional thiols in wine by HS-SPME-GC-MS following extractive alkylation. Molecules 20(7), 12280–12299.
Piano, F., Fracassetti, D, Buica, A., Stander, M., du Toit, W.J., Borsa, D. & Tirelli, A., 2015. Development of a novel liquid/liquid extraction and ultra-performance liquid chromatography tandem mass spectrometry method for the assessment of thiols in South African Sauvignon Blanc wines. Australian Journal of Grape and Wine Research, 21(1), 40–48.
Tominaga, T., Blanchard, L., Darriet, P. & Dubourdieu, D., 2000. A Powerful Aromatic Volatile Thiol, 2-Furanmethanethiol, Exhibiting Roast Coffee Aroma in Wines Made from Several Vitis vinifera Grape Varieties. Journal of Agricultural and Food Chemistry 48(5), 1799–1802.
Tominaga, T., Murat, M.-L. & Dubourdieu, D., 1998. Development of a method for analyzing the volatile thiols involved in the characteristic aroma of wines made from Vitis vinifera L. cv. Sauvignon blanc. Journal of Agricultural and Food Chemistry 46(3), 1044–1048.
Vichi, S., Cortés-Francisco, N. & Caixach, J., 2015. Analysis of volatile thiols in alcoholic beverages by simultaneous derivatization/extraction and liquid chromatography-high resolution mass spectrometry. Food Chemistry 175, 401–408.
Wilson, C.L., 2017. Chemical evaluation and sensory relevance of thiols in South African Chenin Blanc wines. MSc Thesis, Stellenbosch University, Private Bag X1, 7602 Matieland (Stellenbosch), South Africa.
Van Wyngaard, E., 2013. Volatiles playing an important role in South African Sauvignon blanc wines. MSc Thesis, Stellenbosch University, Private Bag X1, 7602 Matieland (Stellenbosch), South Africa
Copyright (c) 2018 South African Society for Enology and Viticulture
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
A copyright form will be e-mailed to the corresponding author when the manuscript has been accepted for publication.
In principle, the Author agrees to the following when he/she signes the copyright agreement:
I hereby assign to the SOUTH AFRICAN SOCIETY FOR ENOLOGY AND VITICULTURE (SASEV) the copyright of the text, tables, figures, supplementary material, illustrations and other information (the Material) submitted with the manuscript to be published in SOUTH AFRICAN JOURNAL OF ENOLOGY AND VITICULTURE (SAJEV) (the "Article"). The copyright becomes effective from the date the Article has been accepted for publication in SAJEV.
This is an open access journal, and the authors and journal should be properly acknowledged, when works are cited.
Author's may use the publishers version for teaching purposes, in books, theses, dissertations, conferences and conference papers.
A copy of the authors' publishers version may also be hosted on the following websites:
- Non-commercial personal webpage or blog.
- Institutional webpage.
- Authors Institutional Repository.
The following notice should accompany such a posting on the website: This is an electronic version of an article published in SAJEV, Volume XXX, number XXX, pages XXX - XXX, DOI. Authors should also supply a hyperlink to the original paper or indicate where the original paper (www.journals.ac.za/index.php/sajev/) may be found.
Authors publishers version, affiliated with the Stellenbosch University will be automatically deposited in the University's Institutional Repository SUNScholar.
Articles as a whole, may not be re-published with another journal.
The following license applies:
Attribution CC BY-NC-ND 4.0
