title: Flavoromics approach in monitoring changes in volatile compounds of virgin rapeseed oil caused by seed roasting.
abstract: Two varieties of rapeseed (one high oleic - containing 76% of oleic acid, and the other - containing 62% of oleic acid) were used to produce virgin (pressed) oil. The rapeseeds were roasted at different temperature/time combinations (at 140-180°C, and for 5-15min); subsequently, oil was pressed from the roasted seeds. The roasting improved the flavour and contributed to a substantial increase in the amount of a potent antioxidant-canolol. The changes in volatile compounds related to roasting conditions were monitored using comprehensive gas chromatography-mass spectrometry (GC×GC-ToFMS), and the key odorants for the non-roasted and roasted seeds oils were determined by gas chromatography-olfactometry (GC-O). The most important compounds determining the flavour of oils obtained from the roasted seeds were dimethyl sulphide, dimethyltrisulfide, 2,3-diethyl-5-methylpyrazine, 2,3-butenedione, octanal, 3-isopropyl-2-methoxypyrazine and phenylacetaldehyde. For the oils obtained from the non-roasted seeds, the dominant compounds were dimethylsulfide, hexanal and octanal. Based on GC×GC-ToFMS and principal component analysis (PCA) of the data, several compounds were identified that were associated with roasting at the highest temperatures regardless of the rapeseed variety: these were, among others, methyl ketones (2-hexanone, 2-heptanone and 2-octanone).
authors.affiliation: Faculty of Food Science and Nutrition, Poznań University of Life Sciences, Wojska Polskiego 31, Poznań 60-624 Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Gracka
authors.affiliation: Faculty of Food Science and Nutrition, Poznań University of Life Sciences, Wojska Polskiego 31, Poznań 60-624 Poland. Electronic address: henrykj@up.poznan.pl.
authors.forename: Henryk H
authors.initials: HH
authors.lastname: Jeleń
authors.affiliation: Faculty of Food Science and Nutrition, Poznań University of Life Sciences, Wojska Polskiego 31, Poznań 60-624 Poland.
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Majcher
authors.affiliation: Faculty of Food Science and Nutrition, Poznań University of Life Sciences, Wojska Polskiego 31, Poznań 60-624 Poland.
authors.forename: Aleksander
authors.initials: A
authors.lastname: Siger
authors.affiliation: Faculty of Food Science and Nutrition, Poznań University of Life Sciences, Wojska Polskiego 31, Poznań 60-624 Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Kaczmarek
mesh_terms: D029741:Brassica rapa / Q000737:chemistry; D005229:Fatty Acids, Monounsaturated; D005504:Food Analysis / Q000379:methods*; D008401:Gas Chromatography-Mass Spectrometry; D006358:Hot Temperature; D064367:Olfactometry; D010938:Plant Oils / Q000737:chemistry*; D000074262:Rapeseed Oil; D012639:Seeds / Q000737:chemistry*; D055549:Volatile Organic Compounds / Q000032:analysis*
chemical_list: D005229:Fatty Acids, Monounsaturated; D010938:Plant Oils; D000074262:Rapeseed Oil; D055549:Volatile Organic Compounds
keywords: Flavoromics; GC×GC-ToFMS; Rapeseed virgin oil; Volatile compounds