Hops are a very important base material for the production of beer. The substance Lupulin, a yellowish powder isolated from the hops cones, is especially responsible for the bitterness and unique taste of a beer. That is why the amount of bitter acids in hops is very important for breweries. Lupulin contains various bitter acids [1], α- (humulone) and β- (lupulone) acids, which vary in different types of hops. Caused by the content of bitter acids, hops are divided into aromatic hops (< 10 % of α-acids) and bitter hops (> 10 % α-acids) [2]. In general, the α- and β-acids are also divided into five homologues. The quantitative analysis of their contents in different hops, as well as the screening for other ingredients was done with TLC and HPLC to compare both methods.
The investigation of different hop types has shown that the amount of α-acid is both dependent on the hop category as well as on the region. Most of the bitter hop samples, except one, have a much higher percentage of α-acid than the other samples. Furthermore, the same hops from different regions do not all have the same amount of acid.
It could also be determined that the β-acid is not related to these criteria and is similar in all hop samples regardless of whether the HPLC or TLC method was used. The amount of α-acid, but not the β-acid, depends on the kind of hop (bitter or aromatic) and the region. Both methods, TLC and HPLC, were used in comparison to quantify α- and β-acids.