| Beide Seiten der vorigen RevisionVorhergehende Überarbeitung | |
| humulus_lupulus_l [2023/07/05 10:49] – andreas | humulus_lupulus_l [2026/07/16 10:53] (aktuell) – andreas |
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| "Application of aroma extract dilution analysis on the volatiles isolated from a Bavarian Pilsner-type beer revealed 40 odor-active constituents in the flavor dilution (FD) factor range of 16−2048, among which ethyl octanoate, (E)-β-damascenone, 2- and 3-methylbutanoic acid, and 4-hydroxy-2,5-dimethyl-3(2H)-furanone showed the highest FD factor of 2048. After quantitation of the 26 odorants showing FD factors ≥128 by stable isotope dilution analysis and determination of their odor thresholds in water, odor acitivity values (OAVs) were calculated. The results indicated ethanol, (E)-β-damascenone, (R)-linalool, acetaldehyde, and ethyl butanoate with the highest OAVs, followed by ethyl 2-methylpropanoate and ethyl 4-methylpentanoate, which was previously unknown in beer. Finally, the overall aroma of the beer could be mimicked for the first time by recombining 22 reference odorants in the same concentrations as they occurred in the beer using ethanol/water as the matrix." \\ | "Application of aroma extract dilution analysis on the volatiles isolated from a Bavarian Pilsner-type beer revealed 40 odor-active constituents in the flavor dilution (FD) factor range of 16−2048, among which ethyl octanoate, (E)-β-damascenone, 2- and 3-methylbutanoic acid, and 4-hydroxy-2,5-dimethyl-3(2H)-furanone showed the highest FD factor of 2048. After quantitation of the 26 odorants showing FD factors ≥128 by stable isotope dilution analysis and determination of their odor thresholds in water, odor acitivity values (OAVs) were calculated. The results indicated ethanol, (E)-β-damascenone, (R)-linalool, acetaldehyde, and ethyl butanoate with the highest OAVs, followed by ethyl 2-methylpropanoate and ethyl 4-methylpentanoate, which was previously unknown in beer. Finally, the overall aroma of the beer could be mimicked for the first time by recombining 22 reference odorants in the same concentrations as they occurred in the beer using ethanol/water as the matrix." \\ |
| [Identification based on quantitative measurements and aroma recombination of the character impact odorants in a Bavarian Pilsner-type beer., Fritsch, H.T., Schieberle, P., Journal of agricultural and food chemistry, Vol.53(19), 2005, 7544-7551] | [Identification based on quantitative measurements and aroma recombination of the character impact odorants in a Bavarian Pilsner-type beer., Fritsch, H.T., Schieberle, P., Journal of agricultural and food chemistry, Vol.53(19), 2005, 7544-7551] |
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| | "A specific extraction with p-hydroxymercuribenzoic acid was performed on four different fresh light-protected lager beers. gas chromatography−olfactometry, gas chromatography−mass spectrometry, and gas chromatography−pulsed-flame photometer detector analyses of the extracts revealed the presence of more than 10 polyfunctional thiols. All of them were absent from wort, suggesting a key role of the H2S excreted by yeasts. 3-Methyl-2-buten-1-thiol, 2-mercapto-3-methylbutanol, 3-mercapto-3-methylbutanol seem to be created from hop allylic alcohols via four different mechanisms: nucleophilic substitution, addition−elimination, and radical anti-Markovnikov or electrophilic Markovnikov additions. 1,4 Addition of hydrogen sulfide to wort α,β-unsaturated aldehydes or ketones may explain the synthesis of 1-mercapto-3-pentanol, 3-mercaptohexanol, and 4-mercapto-4-methyl-2-pentanone through fermentation. Finally, 2-mercaptoethanol, 3-mercaptopropanol, and their corresponding acetates may derive from Ehrlich degradation of sulfur amino acids, while 2-methyl-3-furanthiol should be logically issued from Maillard reactions." \\ |
| | [Vermeulen, Catherine, et al. "Occurrence of polyfunctional thiols in fresh lager beers." Journal of Agricultural and Food Chemistry 54.14 (2006): 5061-5068] |
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| "Extremely strong fruity, black currant-like aromas were detected in beers hopped with some U.S. cultivars. 4-Mercapto-4-methylpentan-2-one (4MMP) was supposed to be the main contributor to the fruity aroma, and the contents between cultivars were investigated. In hop pellets, a negative correlation between 4MMP concentration and copper ion content in hops was observed. 4MMP was detected only in U.S., Australian, and New Zealand cultivars, but no European ones, which are treated with copper-containing fungicides (Bordeaux | "Extremely strong fruity, black currant-like aromas were detected in beers hopped with some U.S. cultivars. 4-Mercapto-4-methylpentan-2-one (4MMP) was supposed to be the main contributor to the fruity aroma, and the contents between cultivars were investigated. In hop pellets, a negative correlation between 4MMP concentration and copper ion content in hops was observed. 4MMP was detected only in U.S., Australian, and New Zealand cultivars, but no European ones, which are treated with copper-containing fungicides (Bordeaux |
