Title: | Headspace solid-phase microextraction and gas chromatographic analysis of low-molecular-weight sulfur volatiles with pulsed flame photometric detection and quantification by a stable isotope dilution assay |
Author(s): | Ullrich S; Neef SK; Schmarr HG; |
Address: | "Dienstleistungszentrum Landlicher Raum (DLR) Rheinpfalz, Institute for Viticulture and Oenology, Neustadt an der Weinstrasse, Germany. Faculty for Chemistry, Food Chemistry, Kaiserslautern University of Technology, Kaiserslautern, Germany. Faculty for Chemistry, Instrumental Analytical Chemistry, University Duisburg-Essen, Essen, Germany" |
ISSN/ISBN: | 1615-9314 (Electronic) 1615-9306 (Linking) |
Abstract: | "Low-molecular-weight volatile sulfur compounds such as thiols, sulfides, disulfides as well as thioacetates cause a sulfidic off-flavor in wines even at low concentration levels. The proposed analytical method for quantification of these compounds in wine is based on headspace solid-phase microextraction, followed by gas chromatographic analysis with sulfur-specific detection using a pulsed flame photometric detector. Robust quantification was achieved via a stable isotope dilution assay using commercial and synthesized deuterated isotopic standards. The necessary chromatographic separation of analytes and isotopic standards benefits from the inverse isotope effect realized on an apolar polydimethylsiloxane stationary phase of increased film thickness. Interferences with sulfur-specific detection in wine caused by sulfur dioxide were minimized by addition of propanal. The method provides adequate validation data, with good repeatability and limits of detection and quantification. It suits the requirements of wine quality management, allowing the control of oenological treatments to counteract an eventual formation of excessively high concentration of such malodorous compounds" |
Keywords: | "Calibration Chromatography, Gas Indicator Dilution Techniques Molecular Weight *Photometry *Solid Phase Microextraction Sulfur Compounds/*analysis Volatile Organic Compounds/*analysis Wine/analysis headspace solid-phase microextraction inverse isotope eff;" |
Notes: | "MedlineUllrich, Sebastian Neef, Sylvia K Schmarr, Hans-Georg eng Germany 2017/12/02 J Sep Sci. 2018 Feb; 41(4):899-909. doi: 10.1002/jssc.201700649. Epub 2017 Dec 27" |