Kvasny Prum. 2006; 52(3): 83-86 | DOI: 10.18832/kp2006007

Evaluation of Barley Crop 2005 - Brewery Section.Peer-reviewed article

Josef ŠKACH, Karel NIKOLAI, Josef PROKEŠ

¹ Výzkumný ústav pivovarský a sladařský, a. s., Praha

² Výzkumný ústav pivovarský a sladařský, Sladařský ústav Brno

In this work, the quality of malts from eight growing regions of the Czech Republic and five spring barley varieties of the year 2005 was monitored. Correlation coefficients were used for the statistical evaluation of the relation between the qualitative parameters of malt and beer quality. Among the interesting correlations found belongs for example the lipoxygenase activity and the dimethylsulphide precursor content in malt or the correlation between the amino nitrogen content and beer colour. There was found a difference in the degree of modification of malts between the South Moravian and the West Bohemian regions. This difference proved also in the attainable degree of attenuation and beer colour. Almost in all cases, a high content of alpha-amino nitrogen was found in hopped worts, even if the protein content in malt was favourably low, which is characteristic for 2005. All beers had a very good filterability; the beta-glucan content in malts was also very favourable. Even under these conditions, a statistically significant correlation was found between the risk potential determined from malt homogeneity by the Carlsberg method and beer filterability. Compared with commonly used analytical parameters, the results indicate a significantly higher predication value of this criterion. The sensorial evaluation of the profile of the brewed beers showed only a minimum difference.In this work, the quality of malts from eight growing regions of the Czech Republic and five spring barley varieties of the year 2005 was monitored. Correlation coefficients were used for the statistical evaluation of the relation between the qualitative parameters of malt and beer quality. Among the interesting correlations found belongs for example the lipoxygenase activity and the dimethylsulphide precursor content in malt or the correlation between the amino nitrogen content and beer colour. There was found a difference in the degree of modification of malts between the South Moravian and the West Bohemian regions. This difference proved also in the attainable degree of attenuation and beer colour. Almost in all cases, a high content of alpha-amino nitrogen was found in hopped worts, even if the protein content in malt was favourably low, which is characteristic for 2005. All beers had a very good filterability; the beta-glucan content in malts was also very favourable. Even under these conditions, a statistically significant correlation was found between the risk potential determined from malt homogeneity by the Carlsberg method and beer filterability. Compared with commonly used analytical parameters, the results indicate a significantly higher predication value of this criterion. The sensorial evaluation of the profile of the brewed beers showed only a minimum difference.

Keywords: barley, malt, quality assessment

Published: March 1, 2006