title: Volatile components of several virgin and refined oils differing in their botanical origin.
abstract: BACKGROUND
  The volatile components of virgin and refined oils whose compositions were very different in terms of oleic, linoleic and linolenic acyl groups were studied by solid phase microextraction (SPME) followed by gas chromatography/mass spectrometry (GC/MS), and their composition of acyl groups was determined by proton nuclear magnetic resonance (1) H NMR. The virgin oils studied were olive, linseed and walnut oils, while the refined oils were sunflower and rapeseed oils.
  
  
  RESULTS
  Large differences were found among the headspace compositions of the virgin oils. These were due in part to compounds that could be considered as markers of different vegetable origins and manufacturing processes, but also to compounds resulting from degradative oxidation of the main acyl group components. By virtue of their being refined, fewer components were present in the refined oils, although differences in their headspaces were found owing to the presence of compounds resulting from oxidation of the determined acyl groups.
  
  
  CONCLUSIONS
  The studied oils show specific characteristics regarding not only their main components, which are well known, but also their volatile components. The latter provide information on some of the processes to which oils have been submitted, on their oxidation level, on their botanical origin and on the compounds responsible for their odour.
authors.affiliation: Food Technology, Lascaray Research Hub, Faculty of Pharmacy, University of the Basque Country (UPV/EHU), Paseo de la Universidad N° 7, E-01006 Vitoria, Spain.
authors.forename: Patricia S
authors.initials: PS
authors.lastname: Uriarte
authors.forename: Encarnación
authors.initials: E
authors.lastname: Goicoechea
authors.forename: María D
authors.initials: MD
authors.lastname: Guillen
mesh_terms: D000215:Acylation; D005227:Fatty Acids / Q000378:metabolism*; D005638:Fruit; D008401:Gas Chromatography-Mass Spectrometry; D015227:Lipid Peroxidation; D009682:Magnetic Resonance Spectroscopy; D019684:Magnoliopsida / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry*; D010938:Plant Oils / Q000737:chemistry*; D012639:Seeds; D055549:Volatile Organic Compounds / Q000032:analysis*
chemical_list: D005227:Fatty Acids; D010936:Plant Extracts; D010938:Plant Oils; D055549:Volatile Organic Compounds