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Qualitative Composition (qualitative + composition)
Selected AbstractsCharacterization of volatile compounds and triacylglycerol profiles of nut oils using SPME-GC-MS and MALDI-TOF-MSEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 2 2009Stefanie Bail Abstract Several nut oil varieties mainly used as culinary and overall healthy food ingredients were subject of the present study. Headspace solid-phase microextraction combined with gas chromatography-mass spectrometry was employed in order to determine the qualitative composition of volatile compounds. Furthermore, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry was used in order to assess the profiles and relative composition of the prevalent triacylglycerols (TAG) within the oils. The headspace of the majority of oil samples was dominated by high contents of acetic acid (up to 42%) and hexanal (up to 32%). As nut oils are typically gained by cold-pressing from previously roasted nuts, characteristic pyrazine derivatives as well as degradation products of long-chain fatty acids were detected. TAG analysis of these oils revealed a quite homogeneous composition dominated by components of the C52 and C54 group composed mainly of oleic (18:1), linoleic (18:2), stearic (18:0) and palmitic (16:0) acid residues representing together between 65 and 95% of the investigated nut oils. The TAG profiles showed characteristic patterns which can be used as ,fingerprints' of the genuine oils. Nut oils exhibiting quite similar fatty acid composition (e.g. hazelnut, pistachio and beech oil) could be clearly discriminated based on TAG showing significant differences between the oils. [source] Volatile constituents of different organs of Psoralea bituminosa L.FLAVOUR AND FRAGRANCE JOURNAL, Issue 2 2004Alessandra Bertoli Abstract The essential oil and SPME samples of the leaves, ,owers and seeds of Psoralea bituminosa L. were analysed by GC and GC,MS. We have investigated also the presence of monoterpene or aliphatic alcohol glucosides. The essential oils showed both qualitative and quantitative differences. The main constituents of the leaf and the ,ower essential oils were caryophyllene (23% and 18%, respectively), , -farnesene (15% and 6%, respectively), and germacrene D (24% and 18%, respectively). Signi,cant amounts (7%) of the same compounds were also directed in the seed essential oil, but tricyclene (11%) and , -pinene (50%) were the most important constituents of this oil. The volatile fractions of remaining leaf aqueous extracts after treatment with , -glucosidase revealed qualitative differences in comparison with the composition of the corresponding essential oils, and high levels of 3-hexen-1-ol (37%) and 1-octen-3-ol (27%) were observed. The SPME analysis of the fresh leaves, ,owers and seeds of P. bituminosa con,rmed the qualitative composition of the volatile oils, even if we detected signi,cative differences in the percentage ratio between monoterpenes and sesquiterpenes in comparison with the oils, where sesquiterpenes were the main components. In fact the variation of the monoterpenes, tricyclene, , -pinene and camphene between the leaf oil and the corresponding headspace sample was remarkable: tricyclene increased from 0.1% to 8%, , -pinene from 0.1% to 16% and camphene from 0.3% to 10% in the SPME samples. Copyright © 2004 John Wiley & Sons, Ltd. [source] Localities and seasonal variations in the chemical composition of essential oils of Satureja montana L. and S. cuneifolia TenFLAVOUR AND FRAGRANCE JOURNAL, Issue 3 2001M. Milos Abstract The essential oils of Satureja montana L. and Satureja cuneifolia Ten. were subjected to detailed GC,MS analysis in order to determine possible similarities between them and also the differences in their chemical compositions, depending on the locality and the stage of development. The plant materials were collected prior to, during and after flowering from three different locations in the central part of Dalmatia (Croatia). For both plants the qualitative composition of the components appeared to be constant in three phenological stages and in three different localities. However, considerable differences were found to exist in the amounts of several compounds. Copyright © 2001 John Wiley & Sons, Ltd. [source] Varietal differences in terpene composition of blackcurrant (Ribes nigrum L) berries by solid phase microextraction/gas chromatographyJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 13 2002Maria Luisa Ruiz del Castillo Abstract Relative amounts of volatile terpenes in berries of 10 different blackcurrant (Ribes nigrum L) cultivars were examined by solid phase microextraction/gas chromatography (SPME/GC). The optimisation of a variety of parameters affecting SPME enabled relative standard deviations from three replicates ranging from 2 to 12% to be achieved. Differences between cultivars in the proportions rather than in the qualitative composition of volatile terpenes were found, and the proportions of some terpenes were especially variable. Furthermore, the enantiomeric ratios of the chiral terpenes were determined for the first time in blackcurrant berries by GC using a column with a stationary phase containing permethylated cyclodextrin (Chirasil-,-Dex). The enantiomeric compositions of the majority of the chiral terpenes varied within a reasonably narrow range. However, the levels of two monoterpene alcohols, terpinen-4-ol and linalool, exhibited considerable variations amongst cultivars. © 2002 Society of Chemical Industry [source] Volatile leaf oil diversity in the narrow range endemic Eucalyptus argutifolia (Myrtaceae) and its widespread congener Eucalyptus obtusifloraBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 4 2009W. JASON KENNINGTON Variation in the qualitative composition of volatile leaf oil was examined in the rare Eucalyptus argutifolia and its widespread congener Eucalyptus obtusiflora. The results revealed that, consistent with the pattern seen with allozymes, E. argutifolia had less variation within populations than E. obtusiflora. Total leaf oil diversity was also significantly lower in the rare species. As found with allozymes, most leaf oil diversity was within populations, but there was also a significant proportion of the variation between populations (25.2% and 27.3% for E. argutifolia and E. obtusiflora, respectively). There were significant associations between phenotypic distance based on leaf oils and geographical distance and between phenotypic and genetic distance across all populations, but these associations were not evident within species. Factors leading to reduced variation in E. argutifolia appear to affect all types of variation, but the relationships between different types of variation within the species are less apparent. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 96, 738,745. [source] | |||||||||||||