50 Years of Progress in Quality of Malting Barley Grown in the Czech Republic

This paper summarizes the results of study of malting and agronomic characteristics of barley varieties grown in the territory of the Czech Republic over the period 1955-2005. Mean year-on-year increase in the grain yield was 53 kg/ha. Mean increase in TGW was 0.177 g/year over the studied period. Accumulation of protein in the studied varieties declined ca by 12%. Varieties from the beginning of the 21st century displayed a 4% higher extract content than those grown in the second half of the 1950s. Mean year-on-year increase in extract (d.m.) was a 0.0641 percentage point. By the end of the 1970s most of the varieties achieved values of diastatic power higher than 300 degrees WK. In the 1970s to 1980s, diastatic power declined to under the level of 300 degrees WK. In the 2nd half of the 1990s and at the beginning of this century, activity of amylolytic enzymes increased considerably in some modern varieties and values of diastatic power frequently moved over 350 degrees WK. Activity of proteolytic enzymes increased by 6%. Mean year-on-year increase in Kolbach index was a 0.1456 percentage point. Value of relative extract at 45 degrees C increased by 3%. Mean year-on-year increase in relative extract at 45 degrees C was a 0.0645 percentage point over the studied period. Value of the apparent final attenuation, a trait characterizing quality of wort composition, increased by 3%. Mean inter-year increase in apparent final attenuation was a 0.0756 percentage point.