title: The comparison of solid phase microextraction-GC and static headspace-GC for determination of solvent residues in vegetable oils.
abstract: The objective of these investigations has been the determination of volatile organic compounds including residue solvents present in vegetable oil samples. Some olive oil, rape oil, sunflower oil, soy-bean oil, pumpkin oil, grape oil, rice oil as well as hazel-nut oil samples were analysed. Among residue solvents the following compounds have been mentioned: acetone, n-hexane, benzene, and toluene. Some experiments for the solid phase microextraction (SPME)-GC-flame ionisation detection (FID) were performed to examine extraction conditions such as fiber exposure time, temperature of extraction, and temperature of desorption. Various SPME fibers such as polydimethylsiloxane, Carboxen/polydimethylsiloxane and polydimethylsiloxane/divinylbenzene coatings were used for the isolation of tested compounds from vegetable oil samples. After optimisation of SPME, real vegetable oil samples were examined using SPME-GC/MS. Based on preliminary experiments the qualitative and quantitative analyses for the determination of acetone, n-hexane, benzene and toluene were performed by SPME-GC-FID and static head-space (SHS)-GC-FID methods. The regression coefficients for calibration curves for the examined compounds were R(2) > or = 0.992. This shows that the used method is linear in the examined concentration range (0.005-0.119 mg/kg for SPME-GC-FID and 0.003-0.728 mg/kg for SHS-GC-FID). Chemical properties of analysed vegetable oils have been characterised by chemometric procedure (cluster analysis).
authors.affiliation: Chair of Environmental Chemistry and Bioanalytics, Faculty of Chemistry, Nicolaus Copernicus University, Torun, Poland. mada@chem.uni.torun.pl
authors.forename: Magdalena
authors.initials: M
authors.lastname: Ligor
authors.forename: Bogusław
authors.initials: B
authors.lastname: Buszewski
mesh_terms: D002849:Chromatography, Gas / Q000379:methods*; D010938:Plant Oils / Q000737:chemistry*; D012680:Sensitivity and Specificity; D012997:Solvents / Q000737:chemistry*; D013696:Temperature
chemical_list: D010938:Plant Oils; D012997:Solvents