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camellia_sinensis_l._kuntze [2022/01/22 15:02]
andreas |
camellia_sinensis_l._kuntze [2023/12/02 13:26] (aktuell)
andreas |
| | {{:linalool_r.jpg|(R)-(-)-linalool}} \\ (R)-(-)-linalool \\ //(flowery)// | {{:nonatrienal_2e4e6z.jpg| (E,E,Z)-2,4,6-nonatrienal }} \\ (E,E,Z)-2,4,6-nonatrienal \\ //(oat flake-like)// | {{geraniol.jpg| geraniol }} \\ geraniol \\ //(sweet floral)// | {{:octa15diene3one.jpg|(Z)-octa-1,5-dien-3-one}} \\ (Z)-octa-1,5-dien-3-one \\ //(green geranium)// | {{:3methyl24nonandione.jpg|3-methyl-2,4-nonanedione}} \\ 3-methyl-2,4-nonanedione \\ //(fruity hay)// | | | {{:linalool_r.jpg|(R)-(-)-linalool}} \\ (R)-(-)-linalool \\ //(flowery)// | {{:nonatrienal_2e4e6z.jpg| (E,E,Z)-2,4,6-nonatrienal }} \\ (E,E,Z)-2,4,6-nonatrienal \\ //(oat flake-like)// | {{geraniol.jpg| geraniol }} \\ geraniol \\ //(sweet floral)// | {{:octa15diene3one.jpg|(Z)-octa-1,5-dien-3-one}} \\ (Z)-octa-1,5-dien-3-one \\ //(green geranium)// | {{:3methyl24nonandione.jpg|3-methyl-2,4-nonanedione}} \\ 3-methyl-2,4-nonanedione \\ //(fruity hay)// | |
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| | "To confirm the identification experiments obtained by this Molecular Sensory Approach, a recombinate was prepared in water consisting of the following odorants in exactly the concentrations as they occured in the tea infusion: 3-methyl-2,4-nonanedione, (E)-β-damascenone, linalool, (Z)-4-heptenal, (E,E,Z)-2,4,6-nonatrienal, (E,Z)-2,6-nonadienal as well as 2- and 3-methylbutanal. The mixture nicely matched the overall green, hay-like aroma of the green tea analyzed. A comparision of the quantitative data with those previously measured for black tea infusion (Darjeeling Gold Auslese), revealed a significant lower concentraion of all aroma compounds in the green tea beverage, except the hay-like smelling 3-methyl-2,4-nonanedione, which was quantified in both teas in the same concentration range. The result corroborates the importance of this compound for the aroma of green tea." \\ |
| "To confirm the identification experiments obtained by this Molecular Sensory Approach, a recombinate was prepared in water consisting of the following odorants in exactly the concentrations as they occured in the tea infusion: 3-methyl-2,4-nonanedione, (E)-β-damascenone, linalool, (Z)-4-heptenal, (E,E,Z)-2,4,6-nonatrienal, (E,Z)-2,6-nonadienal as well as 2- and 3-methylbutanal. The mixture nicely matched the overall green, hay-like aroma of the green tea analyzed. A comparision of the quantitative data with those previously measured for black tea infusion (Darjeeling Gold Auslese), revealed a significant lower concentraion of all aroma compounds in the green tea beverage, except the hay-like smelling 3-methyl-2,4-nonanedione, which was quantified in both teas in the same concentration range. The result corroborates the importance of this compound for the aroma of green tea.2 \\ | |
| [Schuh, Christian, Karola Schmid, and Peter Schieberle. "Aroma active compounds in a green tea infusion (Darjeeling)-Comparison with odorants of a black tea beverage." 8th Wartburg Symposium on Flavor Chemistry and Biology. 2008, 117-122] | [Schuh, Christian, Karola Schmid, and Peter Schieberle. "Aroma active compounds in a green tea infusion (Darjeeling)-Comparison with odorants of a black tea beverage." 8th Wartburg Symposium on Flavor Chemistry and Biology. 2008, 117-122] |
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| In a sensory analysis of four black tea grades, α-ionone, ethyl caprylate, 3-hydroxy-β-damascone, β-ionone, 2(4H)-benzofuranone (dihydroactinidiolide), nonanal, and β-farnesene were positively correlated with sensory attributes (aroma quality) of black tea. \\ | In a sensory analysis of four black tea grades, α-ionone, ethyl caprylate, 3-hydroxy-β-damascone, β-ionone, 2(4H)-benzofuranone (dihydroactinidiolide), nonanal, and β-farnesene were positively correlated with sensory attributes (aroma quality) of black tea. \\ |
| [Hoang, Q.T., et al. "Sensory aroma and related volatile flavor compound profiles of different black tea grades (camellia sinensis) produced in northern Vietnam." in: Fom senses to quality: What can sensory evaluation bring to quality control (2014): 113-119] | [Hoang, Q.T., et al. "Sensory aroma and related volatile flavor compound profiles of different black tea grades (camellia sinensis) produced in northern Vietnam." in: Fom senses to quality: What can sensory evaluation bring to quality control (2014): 113-119] |
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| | "The volatile fractions of three famous Chinese green tea cultivar infusions (Longjing, Maofeng, and Biluochun) were prepared by a combination of the adsorptive column method and the SAFE techniques. The aroma extract dilution analysis (AEDA) applied to the volatile fractions revealed 58 odor-active peaks with flavor dilution (FD) factors between 41 and 47. Forty-six of the odorants, which included six odorants that have not been reported in the literature in Chinese green tea (2-isopropyl-3-methoxypyrazine, 2-ethenyl-3,5-dimethylpyrazine, cis-4,5-epoxy-(E)-2-decenal, 4-ethylguaiacol, (E)-isoeugenol, and 3-phenylpropionic acid), were identified or tentatively identified by GC-MS and GC-O. Among the perceived odorants, 4-hydroxy-2,5-dimethyl-3(2H)-furanone, 3-hydroxy-4,5-dimethyl-2(5H)-furanone, coumarin, vanillin, geraniol, (E)-isoeugenol, and 2-methoxyphenol showed high FD factors in all of the cultivars, irrespective of the cultivar or harvesting season, suggesting that these seven odorants are essential for the aroma of Chinese green tea." \\ |
| | [Baba, Ryoko, and Kenji Kumazawa. "Characterization of the potent odorants contributing to the characteristic aroma of Chinese green tea infusions by aroma extract dilution analysis." Journal of Agricultural and Food Chemistry 62.33 (2014): 8308-8313] |
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| "Black tea volatiles are mainly dependent on the oxidation of tea flavonols during fermentation. Virtually, most alcohols, aliphatic acids, phenols, and carbonyls occur in this stage. The degree of partial fermentation determines the constitution and concentration of major aromas in oolong tea, such as jasmine lactones, nerolidol, and methyl jasmonate. Non-fermented green tea contains abundant tea catechins that give it its unique greenish aroma." \\ | "Black tea volatiles are mainly dependent on the oxidation of tea flavonols during fermentation. Virtually, most alcohols, aliphatic acids, phenols, and carbonyls occur in this stage. The degree of partial fermentation determines the constitution and concentration of major aromas in oolong tea, such as jasmine lactones, nerolidol, and methyl jasmonate. Non-fermented green tea contains abundant tea catechins that give it its unique greenish aroma." \\ |
| "Sensory-guided analysis of the volatile fraction isolated from a freshly prepared green tea beverage (Camellia sinensis; type Jingshan cha) revealed 58 odor-active compounds after application of an aroma extract dilution analysis. Among them, 3-methylnonane-2,4-dione, (Z)-1,5-octadien-3-one, 3-(methylthio)propanal, trans-4,5-epoxy-(E)-2-decenal, methanethiol, dimethyl sulfide, and indole appeared with the highest flavor dilution factors. A quantitation of 42 aroma compounds by means of stable isotope dilution assays followed by the calculation of odor activity values (OAV; ratio of concentration to odor detection threshold) showed 27 key aroma compounds with OAVs ≥ 1. By far, the highest OAV of 458 was calculated for the asparagus-like/putrid smelling dimethyl sulfide followed by (E,E)-2,4-heptadienal." \\ | "Sensory-guided analysis of the volatile fraction isolated from a freshly prepared green tea beverage (Camellia sinensis; type Jingshan cha) revealed 58 odor-active compounds after application of an aroma extract dilution analysis. Among them, 3-methylnonane-2,4-dione, (Z)-1,5-octadien-3-one, 3-(methylthio)propanal, trans-4,5-epoxy-(E)-2-decenal, methanethiol, dimethyl sulfide, and indole appeared with the highest flavor dilution factors. A quantitation of 42 aroma compounds by means of stable isotope dilution assays followed by the calculation of odor activity values (OAV; ratio of concentration to odor detection threshold) showed 27 key aroma compounds with OAVs ≥ 1. By far, the highest OAV of 458 was calculated for the asparagus-like/putrid smelling dimethyl sulfide followed by (E,E)-2,4-heptadienal." \\ |
| [Flaig, Mario, et al. "Characterization of the key odorants in a high-grade Chinese green tea beverage (Camellia sinensis; Jingshan cha) by means of the sensomics approach and elucidation of odorant changes in tea leaves caused by the tea manufacturing process." Journal of agricultural and food chemistry 68.18 (2020): 5168-5179] | [Flaig, Mario, et al. "Characterization of the key odorants in a high-grade Chinese green tea beverage (Camellia sinensis; Jingshan cha) by means of the sensomics approach and elucidation of odorant changes in tea leaves caused by the tea manufacturing process." Journal of agricultural and food chemistry 68.18 (2020): 5168-5179] |
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| | "There were 32 VOCs that contribute to the aroma of green tea, 12 of which contributed to the aroma characteristics of green... Among the above 12 components, 3 were positively correlated with the green score of aroma profile, they were geraniol, cis-3-hexen-1-ol and (E)-2-hexen-1-ol, respectively... cis-3-hexen-1-ol played the leading role in green aroma of green tea." \\ |
| | [Nie, Cong-ning, et al. "Characterization of the effect of cis-3-hexen-1-ol on green tea aroma." Scientific reports 10.1 (2020): 1-15] |
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| | Roller-hot air fixation has been found as the optimal method for generating an intense and long-lasting chestnut-like aroma and floral taste of of green tea with a chestnut-like aroma. Theaspirane, linalool, cedrol, 3-methyl-butanal, trans-β-ionone, and τ-cadinol emerged as key differential volatile compounds between green teas with and without a chestnut-like aroma. \\ |
| | [Wang, Huajie, et al. "Influence of fixation methods on the chestnut-like aroma of green tea and dynamics of key aroma substances." Food Research International 136 (2020): 109479] |
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| | Omission tests showed that (E)-β-damascenone, β-ionone, dihydro-β-ionone, linalool, and geraniol were the key odor-active compounds for the aroma profile of sun-dried black tea. Phenylethyl alcohol, (E)-2-decenal, hexanal, and methyl salicylate were also important to the aroma profile. \\ |
| | [Liu, Cong, et al. "Characterization of key odor-active compounds in Sun-Dried black tea by sensory and instrumental-directed flavor analysis." Foods 11.12 (2022): 1740] [[https://www.mdpi.com/2304-8158/11/12/1740/pdf]] |
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| | "...reduction and addition experiments revealed phenylacetaldehyde, (E,E)-2,4-heptadienal, geraniol, linalool, β-damascenone, 2-methylbutyraldehyde, dimethyl sulfide, and isovaleraldehyde with odor activity values (OAV) > 100 as the characteristic aroma components of F4H [fully fermented black tea] and also as the main contributors to aroma differences between different fermentation degrees." \\ |
| | [Zhou, Jingtao, et al. "Characterizing and Decoding the Effects of Different Fermentation Levels on Key Aroma Substances of Congou Black Tea by Sensomics." Journal of Agricultural and Food Chemistry 71.40 (2023): 14706-14719] |
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| {{:tea_flower.jpg}} \\ | {{:tea_flower.jpg}} \\ |
| Camellia sinensis, Kyoto, Japan \\ | Camellia sinensis, Kyoto, Japan (PD, [[https://creativecommons.org/publicdomain/zero/1.0/deed.de|CC0]]) |
| (PD, [[https://creativecommons.org/publicdomain/zero/1.0/deed.de|CC0]]) | |
| [[https://commons.wikimedia.org/wiki/File:Camellia_sinensis_Japan.JPG|wikimedia commons]] | [[https://commons.wikimedia.org/wiki/File:Camellia_sinensis_Japan.JPG|wikimedia commons]] |
