Analysis and prognosis of bitter acids content in Czech hop varieties – year 2020 and long-term comparisons and trends

Abstract

The article deals with the harvest forecast of the content of bitter acids in Czech hop varieties harvested in 2020. This is presented in the context of long-term trends in the content and composition of bitter acids analogues and the stability of the varietal characteristics in the aforementioned harvest. This analysis is usually available at the end of the calendar year. 180 hop samples were analysed using EBC 7.7 (HPLC) method. The α-acids content in the most important variety of Saaz (3.65% in dry matter) was 12.8% rel. higher than in the 2019 harvest and 4.2% rel. higher than the 28-year average. The α-acids content in Saaz Late (3.23%), Sladek (7.9%), Kazbek (6.4%) and Agnus (12.4%) was significantly higher than both the long-term averages for the varieties and the harvest of 2019. The Premiant (8.0%) variety was close to the long-term average. The ratio of α-/β-acids, the relative content of cohumulone and the relative content of colupulone were consistent with long-term averages of the tested varieties. It was confirmed that the harvest forecast provides timely information on the α-acids content of the given harvest, the results being in good agreement with the values of the final evaluation of all harvested hops.