Influência das proteínas formadoras do glúten na qualidade tecnológica da farinha de trigo para panificação

Abstract

The technological properties of wheat flour define their suitability for different industries and are determined by the content and quality of the gluten proteins, glutenins and gliadins. Knowing that the composition of these proteins is controlled genetically, there is great interest in identifying the glutenin subunits of high and low molecular weight glutenins (HMW-GS and LMW-GS) and ω-gliadins responsible for end-use quality of flour, in order to combine them into new cultivars through breeding. The objective of this study was to evaluate the influence of gluten proteins in the technological quality of bread wheat. Thus, fifteen genotypes belonging to the breeding program of wheat from IAPAR were characterized by the subunit composition of HWS-GS, LWS-GS and ω-gliadins. At the same time, the quality of grain and flour were evaluated by physical, physico-chemical, rheological and baking tests and the results correlated with the presence of specific subunits of gluten protein. It was found that 2 * subunit, encoded by locus Glu-A1 of HMW-GS demonstrated stronger positive influence on the sedimentation volume and protein content compared of the subunit 1. In loci Glu-B1 and Glu-D1, the combination of subunits 17 + 18 and 5+10 resulted in higher water absorption, development time and stability of the dough, while combinations 2 *; 7 + 8; 5 + 10 e 2 *; 17 + 18 ; 5+10 correlated the higher specific volume of breads. For locus Glu-A3 of LMW-GS, subunit c was positively correlated with the volume of sedimentation. In addition, BRS Gralha Azul, BRS Sabiá e BRS Tangará showed translocation of rye, 1A / 1R, responsible for reduced the development time and stability of the mass formed by their flours. With this study, was possible to observe that the evaluated parameters are strongly influenced not only by the subunits of HMW-GS, LMW-GS and ω-gliadins present, but also the combinations between them.