The Czech hop hybrid variety - Part I.

Straková

Fritschová

et al. 2023

Czech bitter varieties were evaluated between 2010 and 2022. Hop varieties displayed an average content of alpha acids between 10.24% w/w (Agnus) and 13.73% w/w (Gaia). Variability below 15%, proved good stability of alpha acids content in all tested bittering hops. All varieties showed a decrease in the content of alpha acids over a period of 13 years of hop cultivation. The highest content of beta acids was determined in Gaia (7.30% w/w). In contrast, the lowest content of beta acids was found in Rubín (3.73% w/w). The new bitter genotypes Uran and 5304 had an average alpha acid content of 11.56% w/w and 10.82% w/w, respectively. Uran showed an average beta acid content of 5.47% w/w and for the genotype 5304 it was 3.61% w/w. In terms of the alpha/beta acids ratio, the hop varieties can be divided into three groups. The first group included the varieties with an alpha/beta acids ratio below 2, i.e. Vital, Boomerang and Gaia. While Agnus and Uran displayed an alpha/beta ratio slightly above 2. The highest alpha/beta ratio above 3 was found in Rubín and the 5303 genotype.

Section: Resultssupporting

confidence: 92%

Evaluation of variability of the content of alpha and beta acids in Czech bittering hop varieties (Humulus lupulus L.)

Straková

Fritschová

et al. 2023

“…In 2001, the first Czech variety of bittering hops was registered (Agnus), showing an alpha acid content of 10% (Nesvadba et al, 2002). Between 2004 and 2010, the Hop Research Institute registered six additional hop varieties (Nesvadba et al, 2013) -Harmonie (2004, Rubín (2007), Vital (2008) -the breeding of which was also aimed at biomedical applications (Krofta et al, 2013) -Kazbek (2008, Bohemie (2010) and Saaz Late (2010). Since 2017, a new generation of hop varieties has been registered.…”

Section: Introductionmentioning

confidence: 99%

Evaluation of Czech hop varieties

Olšovská

Straková

et al. 2021

Self Cite

Czech hop varieties are evaluated as part of maintenance breeding. Every year, this evaluation includes ten mother plants of each hop variety. Yield is determined in kilograms of fresh hops per plant. The t-test is used to determine significance. Results from the years 2014–2019 show that Gaia and Kazbek have the highest yield (3.17 kg/plant and 3.05 kg/plant, respectively). Their yield is higher than that of the Harmonie, Agnus, Bohemie, Premiant, Sládek, Boomerang and Saaz varieties. Saaz has the lowest hop yield, i.e. 1.85 kg/plant. Bor, Saaz Late, Saaz and Sládek show the lowest variability, which ranges between 20.56 and 20.58%. Gaia has the highest variability (34.33%). Gaia also has the highest alpha acid content (12.30%) with a probability of 95% to 99%. Vital and Boomerang have a higher alpha acid content than other Czech hop varieties (11.09% and 10.81%, respectively) with a probability of 99%. Saaz Late (3.42%) and Saaz (3.06%) have the lowest alpha acid content with a probability of 95% to 99%. The variability of alpha acid content is considerably lower than the hop yield variability. Rubín has the lowest year-on-year variability of all Czech varieties (4.81%). Vital and Gaia have a very low variability (5.63% and 5.72%, respectively). A higher variability of alpha acid content was found in Saaz Late, Premiant, Agnus, Saaz, Kazbek, Bor and Harmonie, ranging between 8.01% and 10.21%.

“…Bor, Agnus and Vital (Nesvadba et al, 2013). Still, this is not a significant content of DMX because Vital showed up to a five times higher level of DMX (Krofta et al, 2013). The level of "x+s" (0.06% w/w) was exceeded in Osvald's clone no.…”

Section: Desmethylxanthohumol (Dmx)mentioning

confidence: 91%

Evaluation of original historical clones of hops (Humulus lupulus L.)

Charvátová

Henychová

et al. 2020

Self Cite

The aim of this study was to compare yield and technological parameters of Czech historical hop clones, which were grown in our current climatic conditions. The highest yields from the selected original hop clones were found in “Úštěcký smetaňák” (1.93 t/ha), “Dubský zeleňák” (1.80 t/ha) and “Hřebčí chmel” (1.51 t/ha), which is probably caused by a genetic difference from Saazer hop. On the contrary, a low yield of hops was recorded in “Mastýřovický” (0.50 t/ha). In terms of brewing parameters, the highest contents of valuable alpha acids were detected in Osvald’s clones no. 147 a/I (3.88% w/w), no. 86 (3.71% w/w) together with no. 114 (3.45% w/w), while the lowest level (1.05% w/w) was found in “Hřebčí chmel” and “Úštěcký smetaňák”. The highest contents of essential oils were measured in Osvald’s clone no. 147 a/I (0.77% w/w), “Žatecká populace” (0.68% w/w) and Osvald’s clone no. 126 (0.65% w/w). Vice versa, the clones “Mastýřovický” (0.35% w/w), “Hřebčí chmel” (0.35% w/w) and “Tršický” (0.31% w/w.) exhibited the lowest contents. The evaluated hops displayed a relatively balanced composition of essential oils with the exception of “Dubský zeleňák”, which has an extremely low ratio of farnesene (4.35% rel.), but also a high ratio of selinene (8.95% rel.). Osvald’s clone no. 124b and 126 is genetically identical with the variety of Fuggle. The results show that clones “Hřebčí chmel”, “Úštěcký smetaňák” and “Dubský zeleňák” are different from other clones.