A novel method for separation and identification of ignitable liquid residues in fire debris by gas chromatography and mass spectrometry is presented. Preconcentration of the analytes was carried out using the simple headspace sorptive extraction (HSSE) technique. Polydimethylsiloxane stir bars were used as the enrichment phase, and parameters affecting both the adsorption and desorption stages were carefully optimized. Extraction was carried out at 50°C for 1h. Stir bars were desorbed thermally in the GC injection port, thus avoiding the use of organic solvents. The results for five ignitable liquids, including gasoline and diesel fuel, using HSSE were compared with those obtained with a solid-phase microextraction method, with HSSE appearing as a more sensitive alternative.
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http://dx.doi.org/10.1016/j.forsciint.2014.02.006 | DOI Listing |
Anal Methods
August 2024
Instituto Botánico, Universidad de Castilla-La Mancha, Campus Universitario s/n, Albacete 02071, Spain.
An analytical approach employing headspace sorptive extraction coupled with gas chromatography-mass spectrometry (HSSE-GC-MS) has been successfully developed for the determination of apocarotenoid volatiles arising from the enzymatic activity of carotenoid cleavage enzymes (CCDs) in . The GjCCD4a enzyme derived from gardenia, known for its cleavage specificity at 7,8 and 7',8' double bonds across diverse carotenoid substrates, was utilized as a reference enzyme, using β-carotene as the substrate for the enzymatic activity assays. Optimal headspace conditions for analysis were established following a 5 hours induction period of the recombinant GjCCD4a protein within cells, engineered to produce β-carotene.
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December 2024
State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 Changjiang West Road, Hefei 230036, China.; School of Tea and Food Science and Technology, Anhui Agricultural University, 130 Changjiang West Road, Hefei 230036, China.. Electronic address:
Large-leaf yellow tea (LYT) is processed from both leaves and stems, resulting in a distinctive rice crust-like aroma. Tea stems may contribute differently to the aroma of LYT than leaves. This study aimed to clarify the specific contribution of stems to LYT.
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August 2024
Laboratory of Flavor and Chromatographic Analysis, PROCTA-Post Graduate Program in Food Science and Technology, Federal University of Sergipe, São Cristóvão, Sergipe, Brazil.
Citrus species have undergone immense diversification ever since their ancestral origin. Ponkan and Murcott are two mandarin varieties widely consumed in Brazil and their aroma producing active compounds have not yet been extensively investigated. The present study analyzed the volatile constituents of the Ponkan and Murcott varieties employing the stir bar sorptive extraction (SBSE) technique and gas chromatography-mass spectrometry (GC-MS) analysis for the first time.
View Article and Find Full Text PDFFood Res Int
July 2024
State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei 230036, People's Republic of China; Key Laboratory of Tea Biology and Tea Processing of Ministry of Agriculture and Rural Affairs, Hefei 230036, People's Republic of China; International Joint Laboratory on Tea Chemistry and Health Effects of Ministry of Education, Anhui Agricultural University, Hefei 230036, People's Republic of China. Electronic address:
Chinese Xiaokeng green tea (XKGT) possesses elegant and fascinating aroma characteristics, but its key odorants are still unknown. In this study, 124 volatile compounds in the XKGT infusion were identified by headspace-solid phase microextraction (HS-SPME), stir bar sorptive extraction (SBSE), and solvent extraction-solid phase extraction (SE-SPE) combined with gas chromatography-mass spectrometry (GC-MS). Comparing these three pretreatments, we found HS-SPME was more efficient for headspace compounds while SE-SPE was more efficient for volatiles with higher boiling points.
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August 2024
College of Food Science and Technology, Shanghai Ocean University, Shanghai 201306, China; National R&D Branch Center for Freshwater Aquatic Products Processing Technology (Shanghai), Shanghai 201306, China. Electronic address:
The effects of microwave drying (MD), hot air drying (HAD), vacuum hot air drying (VD), and vacuum freeze drying (VFD) on the volatile profiles of Penaeus vannamei were investigated. A total of 89 and 94 volatile compounds were identified by headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) and monolithic material sorptive extraction gas chromatography-mass spectrometry (MMSE-GC-MS), respectively. Orthogonal partial least squares-discriminant analysis (OPLS-DA) and variable influence on projection (VIP) models were utilized to select characteristic volatiles and key marker compounds (e.
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