Effect of prolonged proteolisis on biochemical composition of the malt wort.

Introduction. Changes in mashing modes can increase extraction of biological compounds from malt. Biochemical composition of the malt wort with prolonged action of proteolytic enzymes during the mashing process was determined. Materials and methods. The raw material composition made from three types of malt: base malt, melanoidin malt and roasted malt. Analysis of the amino acid, carbohydrate and lipid profile in modified proteolytic wort was done by chromatographic methods. Results and discussion. Wort analysis identified 19 amino acids; ten of them were essential amino acids. Total content of amino acids in control wort was 1349 mg/l. Total amino acid content in wort modified by mashing mode 1 increased by 55% to 2096 mg/l. Total content of amino acid in wort modified by mashing mode 2 increased by 90% to 2572 mg/l. Proline content in modified wort was the highest: 437 mg/l in wort modified by mashing mode 1; 568 mg/l in wort modified by mashing mode 2. The high content of leucine, arginine, and phenylalanine was observed in modified wort. The percentage increase in the content of individual amino acids in the modified wort varied significantly. Thus, the content of valine and phenylalanine increased by 101-102%, meanwhile the amount of glycine increased only by 18%. Chromatographic analysis showed that prolonged proteolysis has no effect on the carbohydrate and lipid composition of the wort. Total fatty acid content was in the range from 5.6 to 11.4 mg/l. Difference in total content of fatty acids between samples of modified proteolytic wort was more than 30%. Analysis of wort showed the presence of 11 fatty acids. Palmitic and linoleic acids were predominant in fatty acid profile in modified proteolytic wort: the content of palmitic acid was 38-48%, and the content of linoleic acid (omega-6) was 30-37% from total fatty acid amounts. Carbohydrate profile of the modified proteolytic wort presented by maltose, 53.1%; dextrins, 23.4%; maltotriose, 15.2%, and glucose, 8.3%. Carbohydrate profile of modified proteolytic wort had no difference with traditional malt wort. Conclusions. Modified proteolytic wort after prolonged proteolysis during mashing is a good source of amino acids. Long proteolytic rest significantly increases the content of amino acids in malt wort, which can be further used in the technology of dietary supplement or functional drinks. [ABSTRACT FROM AUTHOR]