Development and optimization of a quantitative analysis of main odorants causing off flavours in cork stoppers using headspace solid‐phase microextraction gas chromatography tandem mass spectrometry

Abstract

A simple and sensitive method was developed and validated to simultaneously separate and determine the 2‐Methoxy‐3,5‐dimethylpyrazine, 2‐Isopropyl‐3‐methoxypyrazine, guaiacol, 2‐Isobutyl‐3‐methoxypyrazine, 2‐Methylisoborneol, geosmin, 2,4,6‐Trichloroanisole, 2,3,4,6‐Tetrachloroanisole, 2,4,6‐Tribromoanisole and Pentachloroanisole in cork stoppers via headspace solid‐phase microextraction (HS‐SPME) coupled with gas chromatography tandem mass spectrometry (GC–MS/MS). The influence of the fibre coating used, the extraction times and temperatures, the sodium chloride additions and the desorption temperatures were investigated. Once done, the optimial HS‐SPME conditions established were divinylbenzene/carboxenpolydimethylsiloxane/polydimethylsiloxane (DVB/CAR/PDMS) fibres, a 50°C extraction temperature, 60‐min extraction time, an ionic strength of 3‐g sodium chlorid and a 290°C desorption temperature. The method showed a good linearity (R2 ≥ 0.994) within the tested range (from 0.1 to 50 ng L−1) for all the compounds. Using TCA‐d10 and MIB‐d3 as internal standards the precision, expressed as repeatability and reproducibility RSD, was <10% in both. Note that the limits of quantifications (LOQs) are below the sensory threshold levels for such compounds in water and wine. Good recoveries were obtained for cork macerates (from 100.4% to 126%) and when compared with other reported methods using HS‐SPME in water and cork stopper samples, the present method had more analytes with the lowest limit of detection for most of the targeted compounds, along with good precision and recovery.

Nickel (0) Complexes as Promising Chemosensors for Detecting the “Cork Taint” in Wine

“…To reduce the financial loss related to the presence of contaminated cork taint, winemakers random control cork stoppers in order to remove the TCA‐containing ones and prevent the wine damage. Considering the concentration range in which TCA can be generally found (ng L −1 ), [15] extremely sensitive and selective analytical techniques are necessary for its determination. To achieve this purpose, numerous chromatographic‐based methodologies have been developed [16] such as gas chromatography‐mass spectroscopy (GC‐MS) analyses [15,17] which require the sample pre‐concentration or solid‐phase microextraction (SPME).…”

Cover Feature: Nickel (0) Complexes as Promising Chemosensors for Detecting the “Cork Taint” in Wine (Eur. J. Inorg. Chem. 9/2022)

“…To reduce the financial loss related to the presence of contaminated cork taint, winemakers random control cork stoppers in order to remove the TCA-containing ones and prevent the wine damage. Considering the concentration range in which TCA can be generally found (ng L À 1 ), [15] extremely sensitive and selective analytical techniques are necessary for its determination. To achieve this purpose, numerous chromatographic-based methodologies have been developed [16] such as gas chromatography-mass spectroscopy (GC-MS) analyses [15,17] which require the sample pre-concentration or solid-phase microextraction (SPME).…”

“…Considering the concentration range in which TCA can be generally found (ng L À 1 ), [15] extremely sensitive and selective analytical techniques are necessary for its determination. To achieve this purpose, numerous chromatographic-based methodologies have been developed [16] such as gas chromatography-mass spectroscopy (GC-MS) analyses [15,17] which require the sample pre-concentration or solid-phase microextraction (SPME). Even if these methods are very sensitive and efficient, the required equipment is notably expensive, especially for small producers.…”

Development, Optimization and Validation of a Sustainable and Quantifiable Methodology for the Determination of 2,4,6-Trichloroanisole, 2,3,4,6-Tetrachloroanisole, 2,4,6-Tribromoanisole, Pentachloroanisole, 2-Methylisoborneole and Geosmin in Air

“…Geosmin (GSM) and 2-methylisoborneol (2MIB) are produced as secondary metabolites by specific microorganisms, including actinomycetes, cyanobacteria (blue-green algae), myxobacteria and fungi. All of these are considered responsible for earthy-musty odours in drinking water and wine [1][2][3][4][5] and represent a serious economic problem for wineries.…”

“…In general, early detection of these compounds in wine, in auxiliary materials involved in the winemaking process or in air, is very important to prevent the contamination of wine [6]. A number of methods have been proposed for the determination of HAs, GSM and 2MIB but they have focused on cork stoppers, water or wine [5,[7][8][9]. Due to the physical and chemical properties of these compounds, gas chromatography coupled to mass spectrometry (GC-MS or GC-MS/MS) has been the preferred technique for their detection and quantification.…”