Kvasny Prum. 2016; 62(10): 294-305 | DOI: 10.18832/kp2016030

Methods for verifying the authenticity of hops - an effective tool against falsificationPeer-reviewed article

Jana OLŠOVSKÁ, Karel KROFTA, Vladimíra JANDOVSKÁ, Josef PATZAK, Karel ŠTĚRBA
1 Výzkumný ústav pivovarský a sladařský, a. s., Lípová 15, 120 44 Praha 2 / Research Institute of Brewing and Malting, plc., Lípová 15, CZ 120 44 Praha 2
2 Chmelařský institut, s.r.o., Kadaňská 2525, 438 46 Žatec / Hop Research Institute, Kadaňská 2525, 438 46 Žatec
3 Katedra analytické chemie, Přírodovědecká fakulta Univerzity Karlovy v Praze, Albertov 6, 128 43 Praha 2 / Department of Analytical Chemistry, Faculty of Science, Charles University in Prague, Albertov 6, CZ 128 43 Prague 2

Falsification attempts occur in almost all commodities and hops is no exception. It is therefore necessary to look for ways to verify its authenticity. This review summarizes modern methods for verifying the authenticity of hops and also provides the latest results of the collaboration of the Research Institute of Brewing and Malting, PLC. and the Hop Research Institute, Ltd., in Žatec. Chemotaxonomic and genetic methods are used to verify the authenticity of hops. Chemical analyzes of newly bred hybrids potentially suitable for Czech beer focused on the content and composition of alpha and beta acids, content and composition of hop oils, and content of total polyphenols were performed and molecular genetic analyses of 150 selected hop genotypes including a world-wide range and breeding material were conducted in 2015. These data were used to construct a comprehensive dendrogram from the tested genotypes. The authors also examined the profiling of Czech hop varieties based on the chemical profiles of proanthocyanidins, and succeeded in using cluster analysis to clearly distinguish the varieties of hops including their genetic relatedness.

Keywords: hop, authenticity, resins, hop oils, polyphenols, DNA markers

Received: July 28, 2016; Accepted: September 13, 2016; Published: October 26, 2016 

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