Characterization of the volatile profile of Brazilian Merlot wines through comprehensive two dimensional gas chromatography time-of-flight mass spectrometric detection

Abstract

Wine aroma is an important characteristic and may be related to certain specific parameters, such as raw material and production process. The complexity of Merlot wine aroma was considered suitable for comprehensive two-dimensional gas chromatography (GC×GC), as this technique offers superior performance when compared to one-dimensional gas chromatography (1D-GC). The profile of volatile compounds of Merlot wine was, for the first time, qualitatively analyzed by HS-SPME-GC×GC with a time-of-flight mass spectrometric detector (TOFMS), resulting in 179 compounds tentatively identified by comparison of experimental GC×GC retention indices and mass spectra with literature 1D-GC data and 155 compounds tentatively identified only by mass spectra comparison. A set of GC×GC experimental retention indices was also, for the first time, presented for a specific inverse set of columns. Esters were present in higher number (94), followed by alcohols (80), ketones (29), acids (29), aldehydes (23), terpenes (23), lactones (16), furans (14), sulfur compounds (9), phenols (7), pyrroles (5), C13-norisoprenoids (3), and pyrans (2). GC×GC/TOFMS parameters were improved and optimal conditions were: a polar (polyethylene glycol)/medium polar (50% phenyl 50% dimethyl arylene siloxane) column set, oven temperature offset of 10 °C, 7s as modulation period and 1.4s of hot pulse duration. Co-elutions came up to 138 compounds in 1D and some of them were resolved in 2D. Among the co-eluted compounds, thirty-three volatiles co-eluted in both 1D and 2D and their tentative identification was possible only due to spectral deconvolution. Some compounds that might have important contribution to aroma notes were included in these superimposed peaks. Structurally organized distribution of compounds in the 2D space was observed for esters, aldehydes and ketones, alcohols, thiols, lactones, acids and also inside subgroups, as occurred with esters and alcohols. The Fischer Ratio was useful for establishing the analytes responsible for the main differences between Merlot and non-Merlot wines. Differentiation among Merlot wines and wines of other grape varieties were mainly perceived through the following components: ethyl dodecanoate, 1-hexanol, ethyl nonanoate, ethyl hexanoate, ethyl decanoate, dehydro-2-methyl-3(2H)thiophenone, 3-methyl butanoic acid, ethyl tetradecanoate, methyl octanoate, 1,4 butanediol, and 6-methyloctan-1-ol.

Identification of complex septic odorants in Huangpu River source water by combining the data from gas chromatography-olfactometry and comprehensive two-dimensional gas chromatography using retention indices

“…Decanal, as a fruity/orange-like odorant, has been detected in drinking water (Bao et al, 1997;Suffet et al, 2004). Undecanal and β-ionone have been reported as typical compounds in algal metabolism processes (Friedrich and Acree, 1998;Watson, 2004), while butyl butanoate was reported as an important flavor compound in fruit and wine industries (Welke et al, 2012;Pino and Febles, 2013). The presence of many algal metabolites should be associated with Taihu Lake, which is located in the upstream of the river.…”

Authenticity Assessment of the “Onisiówka” Nalewka Liqueurs Using Two-Dimensional Gas Chromatography and Sensory Evaluation

“…Therefore, more and more often, two-dimensional gas chromatography (GC×GC) is used to analyze alcoholic beverages. The GC×GC-time-offlight mass spectrometry (TOFMS) technique has found application in wine (Weldegergis et al 2011;Welke et al 2012;Samykanno et al 2013;Bordiga et al 2013), cachaça (Cardeal et al 2008;Cardeal and Marriott 2009;Capobiango et al 2013), and selected spirit beverages (such as vodka, whisky, tequila) (Cardeal and Marriott 2009), also fruit spirit (Villière et al 2012;Capobiango 2015), Japanese sake (Takahashi et al 2016), and Chinese liqueur (Zhu et al 2007;Yao et al 2015) analysis.…”

Optimization of the HS-SPME-GC/MS technique for determining volatile compounds in red wines made from Isabel grapes (Vitis labrusca)

“…The PDMS/CAR/DVB (41 compounds identified) fiber exhibited higher performance than the CAR/PDMS (19 compounds identified) fiber and was selected for use in the other analysis steps of volatiles in wine made from Isabel grapes. The PDMS/CAR/DVB fiber is considered to have intermediate polarity, and previous reports have demonstrated its efficacy in various food matrices, with a higher performance compared to that of other types of polymer films (Welke et al, 2012). This is due to the fiber having three distinct layers, each with a different composition, thus increasing the sorptive capacity of the compounds (Zhang et al, 2011).…”

“…According to the scientific literature two polymer films are the most efficient for extracting volatile compounds from wines; i.e. PDMS/CAR/DVB-polydimethylsiloxane-carboxen-divinylbenzene and CAR/PDMS-carboxen-polydimethylsiloxane (Barros et al, 2012;Noguerol-Pato et al, 2009;Petrozziello et al, 2012;Sagratini et al, 2012;Tao et al, 2008;Weldegergis et al, 2011;Welke et al, 2012Welke et al, , 2014Zhang et al, 2011).…”

“…Wine aroma composition analysis is complex because of the different classes, levels, reactivities and heat sensitivities of its constituents (Bonino et al, 2003;Welke et al, 2012).…”