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citrus_paradisi [2020/08/30 09:58]
andreas |
citrus_paradisi [2021/01/11 22:51]
andreas |
| Naringin is the major flavonoid in grapefruit and gives the grapefruit juice its bitter taste. It is metabolized to the cytochrome P450 inhibiting flavanone naringenin in the human body. [[https://en.wikipedia.org/wiki/Naringin]] | Naringin is the major flavonoid in grapefruit and gives the grapefruit juice its bitter taste. It is metabolized to the cytochrome P450 inhibiting flavanone naringenin in the human body. [[https://en.wikipedia.org/wiki/Naringin]] |
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| "By application of the aroma extract dilution analysis on an extract prepared from fresh grapefruit juice, 37 odor-active compounds were detected in the flavor dilution (FD) factor range of 4-256 and subsequently identified. Among them the highest odor activities (FD factors) were determined for ethyl butanoate, [[https://en.wikipedia.org/wiki/Grapefruit_mercaptan|1-p-menthene-8-thiol]], (Z)-3-hexenal, 4,5-epoxy-(E)-2-decenal, [[http://www.thegoodscentscompany.com/data/rw1036031.html|4-mercapto-4-methylpentane-2-one]], 1-heptene-3-one, and wine lactone. Besides the 5 last mentioned compounds, a total of 13 further odorants were identified for the first time as flavor constituents of grapefruit. The data confirmed results of the literature on the significant contribution of 1-p-menthene-8-thiol in grapefruit aroma but clearly showed that a certain number of further odorants are necessary to elicit the typical grapefruit flavor." \\ [Characterization of the Most Odor-Active Volatiles in Fresh, Hand-Squeezed Juice of Grapefruit (Citrus paradisi Macfayden), Andrea Buettner and Peter Schieberle, J. Agric. Food Chem., 47 (12), 1999, 5189-5193] | "By application of the aroma extract dilution analysis on an extract prepared from fresh grapefruit juice, 37 odor-active compounds were detected in the flavor dilution (FD) factor range of 4-256 and subsequently identified. Among them the highest odor activities (FD factors) were determined for ethyl butanoate, [[https://en.wikipedia.org/wiki/Grapefruit_mercaptan|1-p-menthene-8-thiol]], (Z)-3-hexenal, 4,5-epoxy-(E)-2-decenal, 4-mercapto-4-methylpentane-2-one, 1-heptene-3-one, and wine lactone. Besides the 5 last mentioned compounds, a total of 13 further odorants were identified for the first time as flavor constituents of grapefruit. The data confirmed results of the literature on the significant contribution of 1-p-menthene-8-thiol in grapefruit aroma but clearly showed that a certain number of further odorants are necessary to elicit the typical grapefruit flavor." \\ [Characterization of the Most Odor-Active Volatiles in Fresh, Hand-Squeezed Juice of Grapefruit (Citrus paradisi Macfayden), Andrea Buettner and Peter Schieberle, J. Agric. Food Chem., 47 (12), 1999, 5189-5193] |
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| |{{:grapefruit_mercaptan.jpg| (R)-1-p-menthene-8-thiol }} \\ (R)-1-p-menthene-8-thiol |{{:cassis_pentanone.jpg| 4-mercapto-4-methylpentane-2-one}} \\ 4-mercapto-4-methylpentane-2-one |{{:nootkatone.jpg| (+)-nootkatone }} \\ (+)-nootkatone | | |{{:grapefruit_mercaptan.jpg| (R)-1-p-menthene-8-thiol }} \\ (R)-1-p-menthene-8-thiol |{{:4mmp.png| 4-mercapto-4-methylpentane-2-one}} \\ 4-mercapto-4-methylpentane-2-one |{{:nootkatone.jpg| (+)-nootkatone }} \\ (+)-nootkatone | |
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| Of thirty-eight aroma-active compounds detected in commercial cold-pressed grapefruit oil using GC-O and GC-MS (DB-Wax, DB-1), compounds with the greatest aroma intensities included 1,8-cineole, octanal, dodecanal, trans-4,5-epoxy-(E)-2-decenal, β-sinensal and nootkatone. "The aroma activities of sulphur compounds such as 4-mercapto-4-methyl-2-pentanol and methional were surprisingly low and neither of the two putative grapefruit aroma impact compounds, 4-mercapto-4-methyl-2-pentanone and 1-p-menthene-8-thiol, was detected." \\ | Of thirty-eight aroma-active compounds detected in commercial cold-pressed grapefruit oil using GC-O and GC-MS (DB-Wax, DB-1), compounds with the greatest aroma intensities included 1,8-cineole, octanal, dodecanal, trans-4,5-epoxy-(E)-2-decenal, β-sinensal and nootkatone. "The aroma activities of sulphur compounds such as 4-mercapto-4-methyl-2-pentanol and methional were surprisingly low and neither of the two putative grapefruit aroma impact compounds, 4-mercapto-4-methyl-2-pentanone and 1-p-menthene-8-thiol, was detected." \\ |
| [Characterization of aroma‐impact compounds in cold‐pressed grapefruit oil using time–intensity GC-olfactometry and GC-MS., Lin, J., Rouseff, R.L., Flavour and Fragrance Journal, 16(6), 2001, 457-463] | [Characterization of aroma‐impact compounds in cold‐pressed grapefruit oil using time–intensity GC-olfactometry and GC-MS., Lin, J., Rouseff, R.L., Flavour and Fragrance Journal, 16(6), 2001, 457-463] |
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| "Twenty-five odor-active compounds were quantified in the fresh, hand-squeezed juice of White Marsh seedless grapefruits using stable isotope dilution assays. By calculation of the odor activity values of the odorants (ratio of their concentrations in the juice to their odor thresholds in water) it was shown that the fruity esters ethyl 2-methylpropanoate, ethyl butanoate, and (S)-ethyl 2-methylbutanoate, and the fruity, sweet winelactone, as well as the grassy smelling (Z)-hex-3-enal, and trans-4,5-epoxy-(E)-dec-2-enal with metallic odor, were among the most potent odorants of the fresh grapefruit juice. The typical sulfurous, grapefruit-like odor quality was mainly due to the catty, blackcurrant-like 4-mercapto-4-methylpentan-2-one and the grapefruit-like smelling 1-p-menthene-8-thiol. These findings were confirmed by reconstitution experiments to simulate the aroma of the fresh grapefruit juice." \\ | "Twenty-five odor-active compounds were quantified in the fresh, hand-squeezed juice of White Marsh seedless grapefruits using stable isotope dilution assays. By calculation of the odor activity values of the odorants (ratio of their concentrations in the juice to their odor thresholds in water) it was shown that the fruity esters ethyl 2-methylpropanoate, ethyl butanoate, and (S)-ethyl 2-methylbutanoate, and the fruity, sweet winelactone, as well as the grassy smelling (Z)-hex-3-enal, and trans-4,5-epoxy-(E)-dec-2-enal with metallic odor, were among the most potent odorants of the fresh grapefruit juice. The typical sulfurous, grapefruit-like odor quality was mainly due to the catty, blackcurrant-like 4-mercapto-4-methylpentan-2-one [4MMP; 0.8 mg/kg fruit; OAV 8000] and the grapefruit-like smelling 1-p-menthene-8-thiol. These findings were confirmed by reconstitution experiments to simulate the aroma of the fresh grapefruit juice." \\ |
| | 4MMP produced a more significant difference to the panelists when omitted from the grapefruit recombinant and provided a more authentic, true-to-fruit aroma compared to 1-p-menthene-8-thiol. \\ |
| [Evaluation of key aroma compounds in hand-squeezed grapefruit juice (Citrus paradisi Macfayden) by quantitation and flavor reconstitution experiments., Buettner, A., Schieberle, P., Journal of Agricultural and Food Chemistry, 49(3), 2001, 1358-1363] | [Evaluation of key aroma compounds in hand-squeezed grapefruit juice (Citrus paradisi Macfayden) by quantitation and flavor reconstitution experiments., Buettner, A., Schieberle, P., Journal of Agricultural and Food Chemistry, 49(3), 2001, 1358-1363] |
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