The Experts below are selected from a list of 288 Experts worldwide ranked by ideXlab platform
Michael C. Qian - One of the best experts on this subject based on the ideXlab platform.
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Characterization of Qingke Liquor Aroma from Tibet.
Journal of agricultural and food chemistry, 2019Co-Authors: Yanping Qian, Shuang Chen, Michael C. QianAbstract:Qingke liquor is a very famous Tibetan alcoholic beverage made from “Qingke”, hull-less highland barley, which is exclusively grown in Qinghai-Tibetan Plateau with an average altitude of 4000 m. Qingke liquor made in such an area whose quality or characteristics is a result of its geographic environment, including natural and human culture. In this study, the aroma compounds in two Qingke liquors made from highland barley grown at different elevations (QKH, high elevation, and QKL, low elevation) were compared by aroma extract dilution analysis (AEDA), aroma intensity (Osme), odor activity values (OAVs, ratio of concentration to odor threshold), and aroma recombination. Results revealed Ethyl acetate, Ethyl 2-mEthyl propanoate, Ethyl butanoate, Ethyl 3-mEthyl butanoate, Ethyl Pentanoate, Ethyl hexanoate, Ethyl octanoate, 3-mEthylbutanal, 3-mEthyl-1-butanol, 1-octen-3-ol, β-damascenone, 2,3-butanedione (diacetyl), acetoin, and 2-methoxyphenol (OAV ≥ 10) as important aroma active compounds to Qingke liquors...
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Characterization of the Typical Potent Odorants in Chinese Roasted Sesame-like Flavor Type Liquor by Headspace Solid Phase Microextraction-Aroma Extract Dilution Analysis, with Special Emphasis on Sulfur-Containing Odorants.
Journal of agricultural and food chemistry, 2016Co-Authors: Sha Sha, Michael C. Qian, Shuang Chen, Chengcheng WangAbstract:The aroma profile of Chinese roasted sesame-like flavor type liquor was investigated by means of headspace solid phase microextraction–aroma extract dilution analysis (HS-SPME-AEDA). Sixty-three odor-active regions were detected by HS-SPME-AEDA with flavor dilution (FD) factors >5, and 58 of these were further identified. Among them, Ethyl hexanoate, 2-furfurylthiol, dimEthyl trisulfide, 3-mEthylbutanal, Ethyl butanoate, Ethyl 2-mEthylbutanoate, Ethyl Pentanoate, and Ethyl 4-mEthylPentanoate appeared with the highest FD factors. In particular, eight sulfur-containing odorants were identified to be potentially important to roasted sesame-like flavor type liquor. The concentration of these odor-active compounds was further quantitated by combination of four different quantitative measurements, and 36 odorants had concentrations higher than their corresponding odor thresholds. On the basis of the odor activity values (OAVs), 2-furfurylthiol (OAV 1182), dimEthyl trisulfide (OAV 220), β-damascenone (OAV 116), ...
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Characterization of aroma compounds of chinese "Wuliangye" and "Jiannanchun" liquors by aroma extract dilution analysis.
Journal of agricultural and food chemistry, 2006Co-Authors: Wenlai Fan, Michael C. QianAbstract:Aroma compounds in Chinese “Wuliangye” liquor were identified by gas chromatography−olfactometry (GC−O) after fractionation. A total of 132 odorants were detected by GC−O in Wuliangye liquor on DB-wax and DB-5 columns. Of these, 126 aromas were identified by GC−mass spectrometry (MS). Aroma extract dilution analysis (AEDA) was further employed to identify the most important aroma compounds in “Wuliangye” and “Jiannanchun” liquors. The results showed that esters could be the most important class, especially Ethyl esters. Various alcohols, aldehydes, acetals, alkylpyrazines, furan derivatives, lactones, and sulfur-containing and phenolic compounds were also found to be important. On the basis of flavor dilution (FD) values, the most important aroma compounds in Wuliangye and Jiannanchun liquors could be Ethyl butanoate, Ethyl Pentanoate, Ethyl hexanoate, Ethyl octanoate, butyl hexanoate, Ethyl 3-mEthylbutanoate, hexanoic acid, and 1,1-diethoxy-3-mEthylbutane (FD ≥ 1024). These compounds contributed to fruit...
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Identification of aroma compounds in Chinese ‘Yanghe Daqu’ liquor by normal phase chromatography fractionation followed by gas chromatography[sol ]olfactometry
Flavour and Fragrance Journal, 2006Co-Authors: Wenlai Fan, Michael C. QianAbstract:Aroma compounds in Chinese ‘Yanghe Daqu’ liquor were investigated with normal phase chromatography fractionation followed by gas chromatography–olfactometry (GC–O). Yanghe Daqu liquor was extracted with Freon 11, and then separated into acidic and neutral[sol ]basic fractions. The neutral[sol ]basic fraction was further separated into four fractions, using silica gel normal phase chromatography. Aroma compounds in each fraction were analysed by GC–O and GC–MS. The results showed that Yanghe Daqu liquor aroma was mainly contributed by esters and fatty acids. Among them, Ethyl hexanoate (Osme value =15), Ethyl butanoate (Osme value ≥14) were probably the most important esters, based on their Osme values. In addition, Ethyl octanoate, 3-mEthylbutyl hexanoate and Ethyl Pentanoate could be important (Osme values ≥10). Acids with high Osme value included hexanoic, butanoic, 3-mEthylbutanoic and pentanoic acids. They contributed to sour, acid, cheesy and sweaty aromas. 1-Hexanol and 3-mEthylbutanol also had high Osme values. In addition, 4-Ethylguaiacol, 4-mEthylguaiacol and 4-Ethylphenol were identified in Yanghe Daqu liquor and they contributed to clove, sweet, smoky and goaty aromas. 1,1-Diethoxy ethane, 1,1-diethoxy-2-mEthylpropane and 1,1-diethoxy-3-mEthylbutane were identified and they gave fruity and floral aromas. Copyright © 2005 John Wiley & Sons, Ltd.
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Headspace Solid Phase Microextraction and Gas Chromatography−Olfactometry Dilution Analysis of Young and Aged Chinese “Yanghe Daqu” Liquors
Journal of agricultural and food chemistry, 2005Co-Authors: Wenlai Fan, Michael C. QianAbstract:The aroma compounds of young and aged Chinese “Yanghe Daqu” liquor samples were extracted by solid phase microextraction (SPME) and analyzed by gas chromatography (GC)−olfactometry dilution analysis. The original liquor samples were diluted with deionized water to give a final alcohol content of 14% (v/v). The samples were stepwise diluted (1:1) with 14% (by volume) ethanol−water solution and then extracted by headspace SPME. The samples were preequilibrated at 50 °C for 15 min and extracted with stirring at the same temperature for 30 min prior to injection into GC. The aroma compounds were identified by both GC-MS and GC−olfactometry using DB-Wax and DB-5 columns. The results suggested that esters were the major contributors to Yanghe Daqu liquor aroma. Ethyl hexanoate, Ethyl butanoate, and Ethyl Pentanoate had very high flavor dilution values in both young and aged liquors (FD > 8192). MEthyl hexanoate, Ethyl heptanoate, Ethyl benzoate, and butyl hexanoate could also be very important because of their ...
Jaime Wisniak - One of the best experts on this subject based on the ideXlab platform.
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correlation and prediction of mixing thermodynamic properties of ester containing systems ester alkane and ester ester binary systems and the ternary dodecane Ethyl Pentanoate Ethyl ethanoate
The Journal of Chemical Thermodynamics, 2012Co-Authors: Noelia Perez, Luís Fernández, Francisco Toledo, J A Ortega, Jaime WisniakAbstract:Excess thermodynamic properties V E m and H E m, have been measured for the ternary mixture dodecane + Ethyl Pentanoate + Ethyl ethanoate and for the corresponding binaries dodecane + Ethyl Pentanoate, dodecane + Ethyl ethanoate, Ethyl Pentanoate + Ethyl ethanoate at 298.15 K. All mixtures show endothermic and expansive effects. Experimental results are correlated with a suitable equation whose final form for the excess ternary quantity M E contains the particular contributions of the three binaries (i–j) and a last term corresponding to the ternary, all of them obtained considering fourth-order interactions. The fit goodness for all mixtures is good and comparable to others equations taken from the literature. In this work the dissolution model for the binaries and ternary is analyzed with a special attention to ester–ester binaries whose behaviour is discussed. The application of the UNIFAC group contribution model to estimate the H E m yields acceptable results for the binaries (with the exception of ester–ester) and for the ternary mixture.
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Correlation and prediction of mixing thermodynamic properties of ester-containing systems: Ester + alkane and ester + ester binary systems and the ternary dodecane + Ethyl Pentanoate + Ethyl ethanoate
The Journal of Chemical Thermodynamics, 2012Co-Authors: Noelia Perez, Luís Fernández, Juan Ortega, Francisco Toledo, Jaime WisniakAbstract:Excess thermodynamic properties V E m and H E m, have been measured for the ternary mixture dodecane + Ethyl Pentanoate + Ethyl ethanoate and for the corresponding binaries dodecane + Ethyl Pentanoate, dodecane + Ethyl ethanoate, Ethyl Pentanoate + Ethyl ethanoate at 298.15 K. All mixtures show endothermic and expansive effects. Experimental results are correlated with a suitable equation whose final form for the excess ternary quantity M E contains the particular contributions of the three binaries (i–j) and a last term corresponding to the ternary, all of them obtained considering fourth-order interactions. The fit goodness for all mixtures is good and comparable to others equations taken from the literature. In this work the dissolution model for the binaries and ternary is analyzed with a special attention to ester–ester binaries whose behaviour is discussed. The application of the UNIFAC group contribution model to estimate the H E m yields acceptable results for the binaries (with the exception of ester–ester) and for the ternary mixture.
Wenlai Fan - One of the best experts on this subject based on the ideXlab platform.
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Characterization of aroma compounds of chinese "Wuliangye" and "Jiannanchun" liquors by aroma extract dilution analysis.
Journal of agricultural and food chemistry, 2006Co-Authors: Wenlai Fan, Michael C. QianAbstract:Aroma compounds in Chinese “Wuliangye” liquor were identified by gas chromatography−olfactometry (GC−O) after fractionation. A total of 132 odorants were detected by GC−O in Wuliangye liquor on DB-wax and DB-5 columns. Of these, 126 aromas were identified by GC−mass spectrometry (MS). Aroma extract dilution analysis (AEDA) was further employed to identify the most important aroma compounds in “Wuliangye” and “Jiannanchun” liquors. The results showed that esters could be the most important class, especially Ethyl esters. Various alcohols, aldehydes, acetals, alkylpyrazines, furan derivatives, lactones, and sulfur-containing and phenolic compounds were also found to be important. On the basis of flavor dilution (FD) values, the most important aroma compounds in Wuliangye and Jiannanchun liquors could be Ethyl butanoate, Ethyl Pentanoate, Ethyl hexanoate, Ethyl octanoate, butyl hexanoate, Ethyl 3-mEthylbutanoate, hexanoic acid, and 1,1-diethoxy-3-mEthylbutane (FD ≥ 1024). These compounds contributed to fruit...
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Identification of aroma compounds in Chinese ‘Yanghe Daqu’ liquor by normal phase chromatography fractionation followed by gas chromatography[sol ]olfactometry
Flavour and Fragrance Journal, 2006Co-Authors: Wenlai Fan, Michael C. QianAbstract:Aroma compounds in Chinese ‘Yanghe Daqu’ liquor were investigated with normal phase chromatography fractionation followed by gas chromatography–olfactometry (GC–O). Yanghe Daqu liquor was extracted with Freon 11, and then separated into acidic and neutral[sol ]basic fractions. The neutral[sol ]basic fraction was further separated into four fractions, using silica gel normal phase chromatography. Aroma compounds in each fraction were analysed by GC–O and GC–MS. The results showed that Yanghe Daqu liquor aroma was mainly contributed by esters and fatty acids. Among them, Ethyl hexanoate (Osme value =15), Ethyl butanoate (Osme value ≥14) were probably the most important esters, based on their Osme values. In addition, Ethyl octanoate, 3-mEthylbutyl hexanoate and Ethyl Pentanoate could be important (Osme values ≥10). Acids with high Osme value included hexanoic, butanoic, 3-mEthylbutanoic and pentanoic acids. They contributed to sour, acid, cheesy and sweaty aromas. 1-Hexanol and 3-mEthylbutanol also had high Osme values. In addition, 4-Ethylguaiacol, 4-mEthylguaiacol and 4-Ethylphenol were identified in Yanghe Daqu liquor and they contributed to clove, sweet, smoky and goaty aromas. 1,1-Diethoxy ethane, 1,1-diethoxy-2-mEthylpropane and 1,1-diethoxy-3-mEthylbutane were identified and they gave fruity and floral aromas. Copyright © 2005 John Wiley & Sons, Ltd.
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Headspace Solid Phase Microextraction and Gas Chromatography−Olfactometry Dilution Analysis of Young and Aged Chinese “Yanghe Daqu” Liquors
Journal of agricultural and food chemistry, 2005Co-Authors: Wenlai Fan, Michael C. QianAbstract:The aroma compounds of young and aged Chinese “Yanghe Daqu” liquor samples were extracted by solid phase microextraction (SPME) and analyzed by gas chromatography (GC)−olfactometry dilution analysis. The original liquor samples were diluted with deionized water to give a final alcohol content of 14% (v/v). The samples were stepwise diluted (1:1) with 14% (by volume) ethanol−water solution and then extracted by headspace SPME. The samples were preequilibrated at 50 °C for 15 min and extracted with stirring at the same temperature for 30 min prior to injection into GC. The aroma compounds were identified by both GC-MS and GC−olfactometry using DB-Wax and DB-5 columns. The results suggested that esters were the major contributors to Yanghe Daqu liquor aroma. Ethyl hexanoate, Ethyl butanoate, and Ethyl Pentanoate had very high flavor dilution values in both young and aged liquors (FD > 8192). MEthyl hexanoate, Ethyl heptanoate, Ethyl benzoate, and butyl hexanoate could also be very important because of their ...
Noelia Perez - One of the best experts on this subject based on the ideXlab platform.
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correlation and prediction of mixing thermodynamic properties of ester containing systems ester alkane and ester ester binary systems and the ternary dodecane Ethyl Pentanoate Ethyl ethanoate
The Journal of Chemical Thermodynamics, 2012Co-Authors: Noelia Perez, Luís Fernández, Francisco Toledo, J A Ortega, Jaime WisniakAbstract:Excess thermodynamic properties V E m and H E m, have been measured for the ternary mixture dodecane + Ethyl Pentanoate + Ethyl ethanoate and for the corresponding binaries dodecane + Ethyl Pentanoate, dodecane + Ethyl ethanoate, Ethyl Pentanoate + Ethyl ethanoate at 298.15 K. All mixtures show endothermic and expansive effects. Experimental results are correlated with a suitable equation whose final form for the excess ternary quantity M E contains the particular contributions of the three binaries (i–j) and a last term corresponding to the ternary, all of them obtained considering fourth-order interactions. The fit goodness for all mixtures is good and comparable to others equations taken from the literature. In this work the dissolution model for the binaries and ternary is analyzed with a special attention to ester–ester binaries whose behaviour is discussed. The application of the UNIFAC group contribution model to estimate the H E m yields acceptable results for the binaries (with the exception of ester–ester) and for the ternary mixture.
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Correlation and prediction of mixing thermodynamic properties of ester-containing systems: Ester + alkane and ester + ester binary systems and the ternary dodecane + Ethyl Pentanoate + Ethyl ethanoate
The Journal of Chemical Thermodynamics, 2012Co-Authors: Noelia Perez, Luís Fernández, Juan Ortega, Francisco Toledo, Jaime WisniakAbstract:Excess thermodynamic properties V E m and H E m, have been measured for the ternary mixture dodecane + Ethyl Pentanoate + Ethyl ethanoate and for the corresponding binaries dodecane + Ethyl Pentanoate, dodecane + Ethyl ethanoate, Ethyl Pentanoate + Ethyl ethanoate at 298.15 K. All mixtures show endothermic and expansive effects. Experimental results are correlated with a suitable equation whose final form for the excess ternary quantity M E contains the particular contributions of the three binaries (i–j) and a last term corresponding to the ternary, all of them obtained considering fourth-order interactions. The fit goodness for all mixtures is good and comparable to others equations taken from the literature. In this work the dissolution model for the binaries and ternary is analyzed with a special attention to ester–ester binaries whose behaviour is discussed. The application of the UNIFAC group contribution model to estimate the H E m yields acceptable results for the binaries (with the exception of ester–ester) and for the ternary mixture.
Andrey G. Shmakov - One of the best experts on this subject based on the ideXlab platform.
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Effect of Addition of MEthyl Hexanoate and Ethyl Pentanoate on the Structure of Premixed n-Heptane/Toluene/O2/Ar Flame
Energy & Fuels, 2019Co-Authors: Ksenia N. Osipova, Tatyana A. Bolshova, Oleg P. Korobeinichev, Leonid V. Kuibida, Andrey G. ShmakovAbstract:The effect of adding isomeric esters Ethyl Pentanoate (EPe) and mEthyl hexanoate (MHe) to a model diesel fuel on the chemical structure of its flame has been investigated. A 7/3 (vol) n-heptane/tol...
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Effect of Addition of MEthyl Hexanoate and Ethyl Pentanoate on the Structure of Premixed n‑Heptane/Toluene/O2/Ar Flame
2019Co-Authors: Ksenia N. Osipova, Oleg P. Korobeinichev, Tatyana A. Bolshova, Leonid V. Kuibida, Andrey G. ShmakovAbstract:The effect of adding isomeric esters Ethyl Pentanoate (EPe) and mEthyl hexanoate (MHe) to a model diesel fuel on the chemical structure of its flame has been investigated. A 7/3 (vol) n-heptane/toluene mixture was used as a model diesel fuel. The concentration of EPe or MHe additives to the n-heptane/toluene mixture was 50 vol %. The studied flames were stabilized over a flat burner at a pressure of 1 atm. The structures of three rich (φ = 1.6) flames of n-heptane/toluene/O2/Ar, MHe/n-heptane/toluene/O2/Ar, and EPe/n-heptane/toluene/O2/Ar mixtures were studied. The flame structure data were obtained using the method of molecular beam mass spectrometry (MBMS) with soft electron-impact ionization, gas chromatography–mass spectrometry (GCMS), and microthermocouples. In the flames studied, concentration profiles of more than 30 species were identified and measured, and, in particular, peak concentrations of heavy polycyclic aromatic compounds, the main soot precursors, were measured at a pressure of 1 atm for the first time by MBMS and GCMS techniques. The structures of the n-heptane/toluene and MHe/n-heptane/toluene flames were modeled using published chemical-kinetic mechanisms. For the EPe/n-heptane/toluene mixture, such a mechanism was first developed in this work. Comparison of the experimental and calculated species concentration profiles shows that they are mostly in satisfactory agreement. The key reactions involved in the formation of soot precursors were determined by analyzing the chemical-kinetic mechanisms of oxidation of the investigated fuel blends. The results of the study demonstrate that the applied mechanisms need to be considerably modified to provide an adequate description of the formation and consumption of heavy polycyclic aromatic hydrocarbons
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Photoionization mass spectrometry and modeling study of a low-pressure premixed flame of Ethyl Pentanoate (Ethyl valerate)
Proceedings of the Combustion Institute, 2017Co-Authors: Denis A. Knyazkov, I.e. Gerasimov, Nils Hansen, Andrey G. Shmakov, O.p. KorobeinichevAbstract:Abstract In order to get insight into the decomposition and high-temperature oxidation kinetics of Ethyl Pentanoate in combustion processes, a stoichiometric premixed burner-stabilized flame of Ethyl Pentanoate/O 2 /Ar mixture at low pressure (20 Torr) was investigated by molecular-beam mass spectrometry combined with single-photon ionization by vacuum ultraviolet radiation from the Advanced Light Source (ALS) in Berkeley, CA, USA. Mole fraction profiles of 43 species were measured in the flame and compared with those calculated using a detailed chemical kinetic mechanism proposed by Dayma et al. (2012) for Ethyl Pentanoate oxidation. Although mole fraction profiles of major species and several intermediates were predicted quite accurately by the model, significant discrepancies between the measured and modeled peak mole fractions of many intermediates in the flame were observed. A kinetic analysis of the main reaction pathways of Ethyl Pentanoate oxidation was performed to trace the origins of these discrepancies. It was concluded that the reaction pathways responsible for consumption of primary radicals formed directly from the fuel molecule as well as of the products of successive β-scission reactions should be revised when developing a next-generation combustion model for Ethyl Pentanoate.