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Noelia Tena - One of the best experts on this subject based on the ideXlab platform.
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Volatile Compounds Characterizing Tunisian Chemlali and Chétoui Virgin Olive Oils
J. Agric. Food Chem., 2007Co-Authors: Noelia Tena, Ramó Aparicio-ruiz, Aida Lazzez, Diego L LezAbstract:Abstract: A total of 33 virgin olive oil samples of the two main Tunisian cultivars, Chemlali and Chétoui, were characterized by their volatile compounds. The olive oil samples were obtained from olives harvested at four stages of ripeness in costal and inland farms of different geographical places. Major volatiles, mostly C6 and C5 compounds produced from linolenic and linoleic acids through the lipoxygenase cascade, were quantified by solid-phase microextraction gas chromatography. Mathematical procedures allowed for the determination of the volatiles that not only are able to discriminate the olive oils by their olive cultivar (hexanal, E-2-hexenal, and total ketones) and ripeness (pentanal and 1-penten-3-one) but also contribute to their distinctive aroma. Finally, an electronic nose based on metal oxide sensors was checked for a rapid and at-line implementation of Tunisian olive oil varietal traceability. The classification of the samples by the sensors was explained by their sensitivity to volatiles E-2-hexanal, hexanal, 1-penten-3-one, ethanol, and Z-3-hexenol. Multivariate procedures of discriminant analysis and principal component analysis were used in the study. Keywords: Olive oil; volatiles; SPME GC; MOSs; variety; ripeness.
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Volatile compounds characterizing Tunisian chemlali and chétoui virgin olive oils
Journal of Agricultural and Food Chemistry, 2007Co-Authors: Noelia Tena, Ramó Aparicio-ruiz, Aida Lazzez, Diego Luis García-gonzálezAbstract:A total of 33 virgin olive oil samples of the two main Tunisian cultivars, Chemlali and Chétoui, were characterized by their volatile compounds. The olive oil samples were obtained from olives harvested at four stages of ripeness in costal and inland farms of different geographical places. Major volatiles, mostly C6 and C5 compounds produced from linolenic and linoleic acids through the lipoxygenase cascade, were quantified by solid-phase microextraction-gas chromatography. Mathematical procedures allowed for the determination of the volatiles that not only are able to discriminate the olive oils by their olive cultivar (hexanal, E-2-hexenal, and total ketones) and ripeness (pentanal and 1-penten-3-one) but also contribute to their distinctive aroma. Finally, an electronic nose based on metal oxide sensors was checked for a rapid and at-line implementation of Tunisian olive oil varietal traceability. The classification of the samples by the sensors was explained by their sensitivity to volatiles E-2-hexanal, hexanal, 1-penten-3-one, ethanol, and Z-3-hexenol. Multivariate procedures of discriminant analysis and principal component analysis were used in the study.
Mariana Teodorescu - One of the best experts on this subject based on the ideXlab platform.
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Evaluation of the Carbonyl/Chlorine Interaction Parameters in Pentan-3-One-Chloroalkane Mixtures Using the Disquac Group Contribution Model
Collection of Czechoslovak Chemical Communications, 2020Co-Authors: Mariana Teodorescu, Ivan WichterleAbstract:Thermodynamic behaviour of the eight systems containing Pentan-3-One and a chloroalkane, namely 1-chlorobutane, 1,2-dichloroethane, 1,3-dichloropropane, 1,4-dichlorobutane, trichloromethane, 1,1,1-trichloroethane, tetrachloromethane and 1,1,2,2-tetrachloro- ethane was interpreted in terms of the DISQUAC group contribution model. It was found that quasichemical term for the contact C=O/Cl in the Pentan-3-One-α,ω-dichloroalkane and Pentan-3-One-1,1,1-trichloroethane systems is not negligible. The DISQUAC dispersive interchange parameters for C=O/Cl contact in these systems were evaluated from literature data on linear ketone + 1-chloroalkane systems. It was found that the best description of experimental data for systems containing 1-chlorobutane, trichloromethane, tetrachloromethane, and 1,1,2,2-tetrachloroethane is provided using only dispersive contribution of the C=O/Cl contact. The vapour-liquid equilibrium, GE, and HE data were calculated using the DISQUAC model and compared with experimental data. The model provides a fairly consistent description. The relation between the DISQUAC interchange parameters for C=O/Cl contact and the chloroalkane chain length was established.
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Refractive Indices Measurement and Correlation for Selected Binary Systems of Various Polarities at 25 °C
Journal of Solution Chemistry, 2020Co-Authors: Mariana Teodorescu, Catinca SecuianuAbstract:New refractive indices at 25 °C were measured and are reported here for 19 binary mixtures of Pentan-3-One+1,2-dichloroethane, +1,3-dichloropropane, +1,4-dichlorobutane, +trichloromethane, +1,1,1-trichloroethane, +1,1,2,2-tetrachloroethane; cyclopentanone+1-chlorobutane, +1,1,2,2-tetrachloroethane; cyclohexanone+1,1,2,2-tetrachloroethane; 5-chloro-2-pentanone+n-hexane, +toluene, +ethylbenzene; nitromethane+trichloromethane; and nitromethane or nitroethane, +1,2-dichloroethane, +1,3-dichloropropane, +1,4-dichlorobutane. The experimental refractive index deviations from linear mixing behavior have been evaluated and correlated consistently with the 3-parameter Redlich–Kister equation with good results. The molar refraction was also examined for the systems including Pentan-3-One, cyclopentanone, cyclohexanone and 5-chloro-2-pentanone for which densities and excess molar volumes are available from previous works. Different theoretical (n, ρ) mixing rules were tested for these systems. The excess Gibbs energy G E and excess enthalpy H E values were considered together with the excess molar volumes V E, excess refractive indexes $$ n_{\text{D}}^{\text{E}} $$ , molar refraction R and excess molar refractions R E on mixing in the discussion of the influence of the alkyl chain length or of the nature of the second component in the mixture in terms of molecular interactions.
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Refractive Indices Measurement and Correlation for Selected Binary Systems of Various Polarities at 25 °C
Journal of Solution Chemistry, 2013Co-Authors: Mariana Teodorescu, Catinca SecuianuAbstract:New refractive indices at 25 °C were measured and are reported here for 19 binary mixtures of Pentan-3-One+1,2-dichloroethane, +1,3-dichloropropane, +1,4-dichlorobutane, +trichloromethane, +1,1,1-trichloroethane, +1,1,2,2-tetrachloroethane; cyclopentanone+1-chlorobutane, +1,1,2,2-tetrachloroethane; cyclohexanone+1,1,2,2-tetrachloroethane; 5-chloro-2-pentanone+ n -hexane, +toluene, +ethylbenzene; nitromethane+trichloromethane; and nitromethane or nitroethane, +1,2-dichloroethane, +1,3-dichloropropane, +1,4-dichlorobutane. The experimental refractive index deviations from linear mixing behavior have been evaluated and correlated consistently with the 3-parameter Redlich–Kister equation with good results. The molar refraction was also examined for the systems including Pentan-3-One, cyclopentanone, cyclohexanone and 5-chloro-2-pentanone for which densities and excess molar volumes are available from previous works. Different theoretical ( n , ρ ) mixing rules were tested for these systems. The excess Gibbs energy G ^E and excess enthalpy H ^E values were considered together with the excess molar volumes V ^E, excess refractive indexes $$ n_{\text{D}}^{\text{E}} $$ n D E , molar refraction R and excess molar refractions R ^E on mixing in the discussion of the influence of the alkyl chain length or of the nature of the second component in the mixture in terms of molecular interactions.
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Application of the Predictive UNIFAC Model to the Pentan‐3‐one/Chloroalkane and 5‐Chloro‐2‐pentanone/Hydrocarbon Binary Systems
Chemical Engineering & Technology, 2000Co-Authors: Mariana Teodorescu, Z. Wagner, Ivan WichterleAbstract:The predictive capability of the UNIFAC model by Fredenslund et al. (1977) using the last revised parameters of Hansen et al. (1991) was tested to describe the behavior of the binary systems of Pentan-3-One + chloroalkane and 5-chloro-2-pentanone + hydrocarbon in the range of 313.15–373.15 K at low or moderate pressures. The chloroalkanes under study were 1,2-dichloroethane, 1,3-dichloropropane, 1,4-dichlorobutane, trichloromethane, 1,1,1-trichloroethane, and 1,1,2,2-tetrachloroethane; the hydrocarbons investigated were n-hexane, toluene, and ethylbenzene. The results obtained were compared with the experimental data on VLE and the excess Gibbs energy reported recently by Teodorescu et al. (1997, 1998). The best results in prediction were found for the system of Pentan-3-One + 1,4-dichlorobutane with average deviation up to 0.0041 for the vapor-phase composition and up to 1.83 % in pressure. For the other systems of dichloroalkanes the deviations increase with decreasing size of chloroalkane. For the systems of trichloro- or tetrachloroalkanes the deviations are larger than for dichloroalkanes in both vapor-phase composition and pressure. For the mixtures of 5-chloro-2-pentanone + hydrocarbon the best prediction was obtained for n-hexane (up to 0.0058 in the vapor-phase composition and 5.70 % in pressure). The best description of the excess Gibbs energy is given for 5-chloro-2-pentanone + n-hexane mixture.
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Isothermal vapour–liquid equilibria for Pentan-3-One+1,4- dichlorobutane, +trichloromethane, +1,1,1-trichloroethane, +1,1,2,2-tetrachloroethane binary mixtures
Fluid Phase Equilibria, 1998Co-Authors: Mariana Teodorescu, Ivan WichterleAbstract:Abstract Isothermal vapour–liquid equilibrium data are reported for binary mixtures containing Pentan-3-One with 1,4-dichlorobutane from 343.15 to 373.15 K, trichloromethane from 313.15 to 343.15 K, 1,1,1-trichloroethane from 323.15 to 353.15 K, and 1,1,2,2-tetrachloroethane from 343.15 to 373.15 K. A modified equilibrium still is described. The experimental data were correlated using the Redlich–Kister, Wilson and NRTL models by means of the maximum likelihood method.
Diego L Lez - One of the best experts on this subject based on the ideXlab platform.
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Volatile Compounds Characterizing Tunisian Chemlali and Chétoui Virgin Olive Oils
J. Agric. Food Chem., 2007Co-Authors: Noelia Tena, Ramó Aparicio-ruiz, Aida Lazzez, Diego L LezAbstract:Abstract: A total of 33 virgin olive oil samples of the two main Tunisian cultivars, Chemlali and Chétoui, were characterized by their volatile compounds. The olive oil samples were obtained from olives harvested at four stages of ripeness in costal and inland farms of different geographical places. Major volatiles, mostly C6 and C5 compounds produced from linolenic and linoleic acids through the lipoxygenase cascade, were quantified by solid-phase microextraction gas chromatography. Mathematical procedures allowed for the determination of the volatiles that not only are able to discriminate the olive oils by their olive cultivar (hexanal, E-2-hexenal, and total ketones) and ripeness (pentanal and 1-penten-3-one) but also contribute to their distinctive aroma. Finally, an electronic nose based on metal oxide sensors was checked for a rapid and at-line implementation of Tunisian olive oil varietal traceability. The classification of the samples by the sensors was explained by their sensitivity to volatiles E-2-hexanal, hexanal, 1-penten-3-one, ethanol, and Z-3-hexenol. Multivariate procedures of discriminant analysis and principal component analysis were used in the study. Keywords: Olive oil; volatiles; SPME GC; MOSs; variety; ripeness.
Diego Luis García-gonzález - One of the best experts on this subject based on the ideXlab platform.
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Volatile compounds characterizing Tunisian chemlali and chétoui virgin olive oils
Journal of Agricultural and Food Chemistry, 2007Co-Authors: Noelia Tena, Ramó Aparicio-ruiz, Aida Lazzez, Diego Luis García-gonzálezAbstract:A total of 33 virgin olive oil samples of the two main Tunisian cultivars, Chemlali and Chétoui, were characterized by their volatile compounds. The olive oil samples were obtained from olives harvested at four stages of ripeness in costal and inland farms of different geographical places. Major volatiles, mostly C6 and C5 compounds produced from linolenic and linoleic acids through the lipoxygenase cascade, were quantified by solid-phase microextraction-gas chromatography. Mathematical procedures allowed for the determination of the volatiles that not only are able to discriminate the olive oils by their olive cultivar (hexanal, E-2-hexenal, and total ketones) and ripeness (pentanal and 1-penten-3-one) but also contribute to their distinctive aroma. Finally, an electronic nose based on metal oxide sensors was checked for a rapid and at-line implementation of Tunisian olive oil varietal traceability. The classification of the samples by the sensors was explained by their sensitivity to volatiles E-2-hexanal, hexanal, 1-penten-3-one, ethanol, and Z-3-hexenol. Multivariate procedures of discriminant analysis and principal component analysis were used in the study.
Ramó Aparicio-ruiz - One of the best experts on this subject based on the ideXlab platform.
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Volatile Compounds Characterizing Tunisian Chemlali and Chétoui Virgin Olive Oils
J. Agric. Food Chem., 2007Co-Authors: Noelia Tena, Ramó Aparicio-ruiz, Aida Lazzez, Diego L LezAbstract:Abstract: A total of 33 virgin olive oil samples of the two main Tunisian cultivars, Chemlali and Chétoui, were characterized by their volatile compounds. The olive oil samples were obtained from olives harvested at four stages of ripeness in costal and inland farms of different geographical places. Major volatiles, mostly C6 and C5 compounds produced from linolenic and linoleic acids through the lipoxygenase cascade, were quantified by solid-phase microextraction gas chromatography. Mathematical procedures allowed for the determination of the volatiles that not only are able to discriminate the olive oils by their olive cultivar (hexanal, E-2-hexenal, and total ketones) and ripeness (pentanal and 1-penten-3-one) but also contribute to their distinctive aroma. Finally, an electronic nose based on metal oxide sensors was checked for a rapid and at-line implementation of Tunisian olive oil varietal traceability. The classification of the samples by the sensors was explained by their sensitivity to volatiles E-2-hexanal, hexanal, 1-penten-3-one, ethanol, and Z-3-hexenol. Multivariate procedures of discriminant analysis and principal component analysis were used in the study. Keywords: Olive oil; volatiles; SPME GC; MOSs; variety; ripeness.
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Volatile compounds characterizing Tunisian chemlali and chétoui virgin olive oils
Journal of Agricultural and Food Chemistry, 2007Co-Authors: Noelia Tena, Ramó Aparicio-ruiz, Aida Lazzez, Diego Luis García-gonzálezAbstract:A total of 33 virgin olive oil samples of the two main Tunisian cultivars, Chemlali and Chétoui, were characterized by their volatile compounds. The olive oil samples were obtained from olives harvested at four stages of ripeness in costal and inland farms of different geographical places. Major volatiles, mostly C6 and C5 compounds produced from linolenic and linoleic acids through the lipoxygenase cascade, were quantified by solid-phase microextraction-gas chromatography. Mathematical procedures allowed for the determination of the volatiles that not only are able to discriminate the olive oils by their olive cultivar (hexanal, E-2-hexenal, and total ketones) and ripeness (pentanal and 1-penten-3-one) but also contribute to their distinctive aroma. Finally, an electronic nose based on metal oxide sensors was checked for a rapid and at-line implementation of Tunisian olive oil varietal traceability. The classification of the samples by the sensors was explained by their sensitivity to volatiles E-2-hexanal, hexanal, 1-penten-3-one, ethanol, and Z-3-hexenol. Multivariate procedures of discriminant analysis and principal component analysis were used in the study.
