Kvasny Prum. 2013; 59(1): 2-13 | DOI: 10.18832/kp2013001

The Czech hop hybrid variety - Part I.Peer-reviewed article

Karel KROFTA, Josef PATZAK, Vladimír NESVADBA, Alexandr MIKYŠKA, Martin SLABÝ, Pavel ČEJKA

¹ Chmelařský institut s. r. o., Kadaňská 2525, 438 46 Žatec

² Výzkumný ústav pivovarský a sladařský, a.s., Lípová 15, 120 44 Praha 2

The Vital hop variety was first registered in 2008. Vital is genetically most related to Agnus, another Czech variety. The yield potential is 2.0 to 2.5 t/ha. With respect to its content of α-bitter acids of 10 to 15 % it belongs to the bitter cultivars. Both, the contents of β-bitter acids, in the range of 6 to 10 % and the total hop oils of 1.5 to 2.5 % are high. The contents of farnesene and humulene of up to 5 % rel. are characteristic for the hop oils compositions. The content of selinene was 7 to 15 % rel. The most significant characteristic of the variety is the high content of desmethylxanthohumol (DMX). DMX is precursor of 8-prenylnaringenin, one of the most efficient phytoestrogen currently known. Because of its high content of this compound the Vital hop variety could also be a prospective cultivar for non-brewing applications in pharmacy or for the production of food supplements. In fresh green cones DMX contents of 0.50 to 0.70 % were found. In the course of drying significant losses of DMX occur due to its chemical instability. Under the most common drying temperatures of 55-60 °C the loss of DMX is more than 30 % rel. In the case of utilizing this hop variety for non-brewing purposes, specific modes of green hops processing such as gentle drying and storage of dried hops in air conditioned warehouses until final processing such as pelletizing or extraction would be necessary.The Vital hop variety was first registered in 2008. Vital is genetically most related to Agnus, another Czech variety. The yield potential is 2.0 to 2.5 t/ha. With respect to its content of α-bitter acids of 10 to 15 % it belongs to the bitter cultivars. Both, the contents of β-bitter acids, in the range of 6 to 10 % and the total hop oils of 1.5 to 2.5 % are high. The contents of farnesene and humulene of up to 5 % rel. are characteristic for the hop oils compositions. The content of selinene was 7 to 15 % rel. The most significant characteristic of the variety is the high content of desmethylxanthohumol (DMX). DMX is precursor of 8-prenylnaringenin, one of the most efficient phytoestrogen currently known. Because of its high content of this compound the Vital hop variety could also be a prospective cultivar for non-brewing applications in pharmacy or for the production of food supplements. In fresh green cones DMX contents of 0.50 to 0.70 % were found. In the course of drying significant losses of DMX occur due to its chemical instability. Under the most common drying temperatures of 55-60 °C the loss of DMX is more than 30 % rel. In the case of utilizing this hop variety for non-brewing purposes, specific modes of green hops processing such as gentle drying and storage of dried hops in air conditioned warehouses until final processing such as pelletizing or extraction would be necessary.

Keywords: hop (Humulus lupulus L.), alpha acids, hop oils, prenylflavonoids, DMX, DNA, genome

Accepted: December 6, 2012; Published: January 1, 2013