Iso-α-acids and reduced iso-α-acids (rho, tetra, hexa) in beer
by HPLC
Iso-α-acids and reduced iso-α-acids (rho, tetra, hexa) in beer
by HPLC
Iso-α-acids and reduced iso-α-acids (rho, tetra, hexa) in beer by HPLC
- Application Number
- 127820
- Method
- HPLC
- Results
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Legend:
Chromatograms A - standard mix of iso-α-acids (rho, iso, tetra) B - beer sample with iso-α-acids (rho) C - standard mix of iso-α-acids (hexa) Peaks R1 - ρ-isocohumulone R2 - (6S)-cis-ρ-isocohumulone R3 - (6R)-cis-ρ-isohumulone R4 - ρ-iso-n/ad-humulone R5 - ρ-iso-n/ad-humulone R6 - (6S)-cis-ρ-isohumulone I2 - trans-isocohumulone I4 - trans-iso-iso-n/ad-humulone T1 - cis-tetrahydroisocohumulone T2 - trans-tetrahydroisocohumulone T3 - cis-tetrahydroisoadhumulone T4 - cis-tetrahydroisohumulone T5 - trans-tetrahydroisoadhumulone T6 - trans-tetrahydroisohumulone H1 - (6R)-cis-hexahydroisocohumulone H2 - (6R)-cis-hexahydroisohumulone H3 - (6S)-cis-hexahydroisocohumulone H4 - hexahydroiso-n/ad-humulone H5 - hexahydroiso-n/ad-humulone H6 - (6S)-cis-hexahydroisohumulone.gif)
- Substances
- ρ-isocohumulone; (6S)-cis-ρ-isocohumulone; (6R)-cis-ρ-isohumulone; ρ-iso-n/ad-humulone; ρ-iso-n/ad-humulone; (6S)-cis-ρ-isohumulone; trans-isocohumulone; trans-iso-iso-n/ad-humulone; cis-tetrahydroisocohumulone; trans-tetrahydroisocohumulone; cis-tetrahydroisoadhumulone; cis-tetrahydroisohumulone; trans-tetrahydroisoadhumulone; trans-tetrahydroisohumulone; (6R)-cis-hexahydroisocohumulone; (6R)-cis-hexahydroisohumulone; (6S)-cis-hexahydroisocohumulone; hexahydroiso-n/ad-humulone; hexahydroiso-n/ad-humulone; (6S)-cis-hexahydroisohumulone
- Product(s)
Phase REF Webshop NUCLEODUR C18 Isis
760404.40
NUCLEODUR C18 Isis
761911.30
- Matrix
- beer
- Sample(s)
Preparation of standard mixes: See the cited literature.
Preparation of beer sample
For degassing beer a drop of 1-octanol (about 10 µL) is placed at the bottom of a 250 mL glass beaker. About 50 mL beer is poured into the beaker, which is transferred to an ultrasonic bath and degassed for 15 min. 750 µL degassed beer is transferred to a 2 mL autosampler vial. 750 µL methanol is addded and the vial is closed. After mixing by inversion, the vial is transferred to the autosampler. The addition of methanol precipitates compounds in the beer. Before injection the precipitate (haze) should be allowed to settle. (Alternative: centrifugation, 3000 x g, 15 min, ambient temperature)
- Conditions
- Eluent A: methanol
- Eluent B: 300 mL acetonitrile + 700 mL 1 % citric acid buffer (pH 7.0)
- Gradient: 85 % B for 5 min, 85 - 20 % B in 25 min, 20 % B for 3 min, 20 - 85 % B in 2 min, 85 % B for 10 min
- Flow rate: 1.0 mL/min
- Temperature: 35 °C
- Detection
- UV, 270 nm
- Note
- The author successfully developed this application note according the regulation of Analytica-EBC, Section 9 Beer, Method 9.47 with NUCLEODUR C18 Isis. Other tested C18 and C8 columns could not separate all substances.
- Author
- Tischliar, M.
- Source
- Forschungszentrum Weihenstephan für Brau- und Lebensmittelqualität BLQ, Instrumentelle Analytik, Freising, Germany 2016
- Disclaimer
- Concerning questions to literature applications please contact the cited author/s. Chemicals mentioned in applications are not manufactured or sold by MACHEREY-NAGEL. Applications mentioned in MACHEREY-NAGEL literature or databases are provided for informational purposes only. MACHEREY-NAGEL does not warrant that all applications have been tested in MACHEREY-NAGEL laboratories using MACHEREY-NAGEL products. MACHEREY-NAGEL does not warrant the correctness of the applications.