Kvasny Prum. 2011; 57(7-8): 236-241 | DOI: 10.18832/kp2011025

Determination of extract in barley grain by the enzymatic way.Peer-reviewed article

Gregor TOMÁŠ, Radim CERKAL, Luděk HŘIVNA, Viera ŠOTTNÍKOVÁ

¹ Ústav technologie potravin, Agronomická fakulta, Mendelova univerzita v Brně

² Ústav pěstování, šlechtění rostlin a rostlinolékařství, Agronomická fakulta, Mendelova univerzita v Brně

The Bishop correlation is used in order to obtain fast information regarding the extract of barley grain. The Bishop correlation was developed experimentally and has been modified several times to adjust to the requirements of the modern malting practice. Establishment of the exact content of the extractive grain substances is time-consuming, and it is carried out after malting the grain in the congress wort according to the EBC method 4.5.1. The aim of this study was to establish the extract directly from the spring barley grain by the means of enzymatic preparations based on proteases, cellulases, xylanases, β-glucanases, and amylases. These enzymes decompose individual components of the grain in a similar way the natural enzymes in malt do, therefore, there is no need to malt the grain. The barley grain does not contain the necessary enzymes that are able to break down the extractive grain substances. The preparation of barley malt containing active enzymatic apparatus takes approximately 10 days in the micro malt house. The company GENENCOR International ® has developed a complete set of enzymes for extractive cereal grain substances decomposition. It was experimentally verified that the following sequencing of the enzymes was the most favorable cellulase - xylanase - β-glucanase - α-amylase - β-amylase together with protease. Application of these enzymes into a solution containing crushed grain (so-called preliminary crushing) and by filtration of this solution, wort is created. Its composition is similar to that of the conventional wort obtained from malt. By using the 1.13 factor, correction to values nearing the values of the extract in malt according to EBC is achieved.The Bishop correlation is used in order to obtain fast information regarding the extract of barley grain. The Bishop correlation was developed experimentally and has been modified several times to adjust to the requirements of the modern malting practice. Establishment of the exact content of the extractive grain substances is time-consuming, and it is carried out after malting the grain in the congress wort according to the EBC method 4.5.1. The aim of this study was to establish the extract directly from the spring barley grain by the means of enzymatic preparations based on proteases, cellulases, xylanases, β-glucanases, and amylases. These enzymes decompose individual components of the grain in a similar way the natural enzymes in malt do, therefore, there is no need to malt the grain. The barley grain does not contain the necessary enzymes that are able to break down the extractive grain substances. The preparation of barley malt containing active enzymatic apparatus takes approximately 10 days in the micro malt house. The company GENENCOR International ® has developed a complete set of enzymes for extractive cereal grain substances decomposition. It was experimentally verified that the following sequencing of the enzymes was the most favorable cellulase - xylanase - β-glucanase - α-amylase - β-amylase together with protease. Application of these enzymes into a solution containing crushed grain (so-called preliminary crushing) and by filtration of this solution, wort is created. Its composition is similar to that of the conventional wort obtained from malt. By using the 1.13 factor, correction to values nearing the values of the extract in malt according to EBC is achieved.

Keywords: barley, malt, extract, Bishop, enzymes, wort, EBC

Received: May 12, 2011; Accepted: June 23, 2011; Published: July 1, 2011