Separation and specific determination of the most important individual components of the bittering substance fraction of hops and hop products by high-pressure liquid chromatography (HPLC) provides deeper insight into the composition of these fractions, which for example, may be utilized for the characterization of hop varieties. The specific analysis data aid in the determination of yield and the influence of hop processing methods on quality. The quantity of hops added based exclusively on the α-acid content determined by HPLC can, in certain instances, lead to variations in the bitterness of the finished beer. The prerequisite for the application of the HPLC method in this area is the availability of suitable calibration standards.
Hops and hop products intended for use in beer brewing or elsewhere in the food industry
After milling, hops and hop powder products are extracted using a diethyl ether/methanol mixture and a hydrochloric acid solution. The α-acids and β-acids dissolved in the ether phase are separated using reversed phase high-pressure liquid chromatography (RP-HPLC) and measured spectrophotometrically at a wavelength of 314 nm.
Hop extracts are dissolved in methanol. The α-acids and β-acids dissolved in the methanol are separated using reversed phase high pressure liquid chromatography (RP-HPLC) and measured spectrophotometrically at a wavelength of 314 nm.