FUNCTIONAL TECHNOLOGICAL PROPERTIES AND ELECTROPHORETIC COMPOSITION OF MODIFIED WHEAT GLUTEN

This article provides data on correlation between functional technological properties of native and modified wheat gluten and its specific molecular weights, with an objective to develop control methods for adjustment of physical and chemical specifications of protein products. We used methods for chemical composition analysis in protein products, protein electrophoresis (PAGE), and DWG modifications. We used enzymatic preparations (EP) for DWG properties modification: endoprotease EP (Protamex (R)) and Flavourzyme 500 MG, which contains both endoprotease and endopeptidase simultaneously. It is shown that native DWG underperforms in its functional technological properties in comparison to sodium caseinate, soy flour, soy concentrate, and egg albumin, therefore its properties are modified by limited proteolysis with protein hydrolysis degree of 1.10-3.41%. Our findings indicate that hydrolysis duration might be used to control DWG properties: to increase solubility, foam forming capacity (FFS) up to the respective values demonstrated by egg albumin, and at the same time, to reduce water-and fat-binding capacity and fat emulsifying capacity. DWG with improved FFS contains single-chain polypeptides, both with low molecular weight (ME) (under 40 kD.), and with medium ME (40-60 kD.). Among multi-chain peptides with more pronounced foam-forming capacity, presence of single-chain peptides with low ME (12-16 kD.) seems more preferable than polypeptides with medium (27-39 kD.) and high ME (69-108 kD.). Revealed regularities in correlation of DWG functional properties and ME / composition specificity are intended to be used in DWG modification for further various applications in food industry, mostly for pastries production.