EVALUATION OF THE CONTENT AND COMPOSITION OF ESSENTIAL OIL OF AROMATIC AND BITTER HOP VARIETIES

For hundreds of years, hops, as the main ingredient in brewing beer, have given the beverage not only its traditional bitterness, but also its unique hop aroma. This is due to the variety of essential oils and aromatic substances contained in hop cones, which give beer its special hop aroma. The aim of our work was to investigate the properties and evaluate the variability of the content and composition of essential oil in eleven aromatic and bitter hop varieties, with a particular focus on their genetic stability and suitability for brewing. The hop varieties studied show significant variability in essential oil content, which is crucial for brewing, with an average ranging from 0.42 to 1.87 ml/100 g of dry hops. The maximum content of essential oil (1.98 ml/100 g of dry hops) was found in the cones of the new bitter hop variety Vytiaz, and the minimum amount is found in the cones of the finely aromatic Žatec-type varieties Klon 18 and Zlato Polissya (from 0.32 to 0.58 ml/100 g). Among the aromatic varieties, the maximum content of essential oil was determined in the Zagrava variety with a range of variation (R) from 1.01 to 1.88 ml/100 g of dry hops, with an average value of 1.25 ml/100 g. The majority of the components of hop essential oil are hydrocarbons and are represented by terpenes: monoterpenoids – myrcene and sesquiterpenoids – caryophyllene, humulene and farnesene, which together constitute 67.9-84.0 % of its total content. Aromatic varieties demonstrated a myrcene content typical of European varieties. The farnesene content varied significantly, ranging from 0.3 to 19.8%, with the highest content found in the Klon 18, Zlato Polissya, and National varieties and the bitter Promin variety. The humulene content ranged from 15.5 to 27.7 %. The study showed that, despite annual fluctuations, the content and composition of essential oil remained within the passport data declared for the variety. The study demonstrates the genetic basis of the composition of essential oil in hops, highlighting its potential as a biochemical criterion for variety identification. The results of the study provide valuable information on sustainable cultivation and optimal use of hops in the brewing industry.