title: Quantitative analysis of volatiles in edible oils following accelerated oxidation using broad spectrum isotope standards.
abstract: Analysis of food volatiles generated by processing are widely reported but comparisons across studies is challenging in part because most reports are inherently semi-quantitative for most analytes due to limited availability of chemical standards. We recently introduced a novel strategy for creation of broad spectrum isotopic standards for accurate quantitative food chemical analysis. Here we apply the principle to quantification of 25 volatiles in seven thermally oxidised edible oils. After extended oxidation, total volatiles of high n-3 oils (flax, fish, cod liver) were 120-170 mg/kg while low n-3 vegetable oils were <50mg/kg. Separate experiments on thermal degradation of d5-ethyl linolenate indicate that off-aroma volatiles originate throughout the n-3 molecule and not solely the n-3 terminal end. These data represent the first report using broad-spectrum isotopically labelled standards for quantitative characterisation of processing-induced volatile generation across related foodstuffs, and verify the origin of specific volatiles from parent n-3 fatty acids.
authors.affiliation: Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA.
authors.forename: Pilar
authors.initials: P
authors.lastname: Gómez-Cortés
authors.affiliation: Department of Food Science, Cornell University, Ithaca, NY 14853, USA; New York State Agricultural Experiment Station, Geneva, NY 14456, USA.
authors.forename: Gavin L
authors.initials: GL
authors.lastname: Sacks
authors.affiliation: Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA; Department of Food Science, Cornell University, Ithaca, NY 14853, USA. Electronic address: jtb4@cornell.edu.
authors.forename: J Thomas
authors.initials: JT
authors.lastname: Brenna
mesh_terms: D002247:Carbon Isotopes; D004042:Dietary Fats, Unsaturated / Q000032:analysis*; D005227:Fatty Acids / Q000032:analysis; D015525:Fatty Acids, Omega-3 / Q000032:analysis; D008401:Gas Chromatography-Mass Spectrometry; D006358:Hot Temperature; D009822:Oils, Volatile / Q000032:analysis*; D010084:Oxidation-Reduction; D010938:Plant Oils / Q000032:analysis
chemical_list: D002247:Carbon Isotopes; D004042:Dietary Fats, Unsaturated; D005227:Fatty Acids; D015525:Fatty Acids, Omega-3; D009822:Oils, Volatile; D010938:Plant Oils
keywords: Autoxidation; Broad spectrum isotopic standards; HS-SPME-GC/TOF-MS; Off-flavours; Terminal end; n-3 fatty acids