EFFECTS OF GLIADIN/GLUTENIN AND HMW-GS/LMW-GS RATIO ON DOUGH RHEOLOGICAL PROPERTIES AND BREAD-MAKING POTENTIAL OF WHEAT VARIETIES

The gliadin/glutenin ratio of 15 diverse wheat varieties ranged from 0.75 to 1.16, whereas the high molecular weight glutenin subunits (HMW-GS) to low molecular weight glutenin subunits (LMW-GS) ratio of these varieties ranged from 0.31 to 0.93. Gliadin/glutenin ratio showed a significant negative relationship with specific loaf volume (r=-0.73), dough development time (DDT; r=-0.73), dough stability (r=-0.79) and positive associations with LMW quantity (r=0.72). Mixolab classified the wheat varieties into two groups on the basis of HMW-GS located at Glu-A1 and Glu-D1. Wheat varieties HI 977 and DBW 16 with subunits 2* and 5 +10 at Glu-A1 and Glu-D1, respectively, exhibited the characteristics of extra strong doughs with longer DDT of 8.3and 7.2min, and higher dough stability values of 9.1 and 8.6min, respectively. Wheat varieties C 306, HW 2004 with null allele at Glu-A1 and 2+12 at Glu-D1, in contrast, were weak as they developed quickly, with low dough stability (4min). Practical ApplicationsBread has been one of the principal forms of food for man from the earliest times. Bread quality is determined by the composition and molecular structure of gluten which in turn controls the interactions of gluten subfractions during processing. Rheological properties, microstructure of gluten, gliadin/glutenin ratio and HMW-GS/LMW-GS ratio have been found to be associated with bread-making quality of wheat varieties. The research implications may be utilized both by industry personnel as well as researchers to assess the bread-making quality of wheat varieties.