132 Experimental bake test for wheat breeding program.

M. S. CALEY, O. K. Chung, and J. B. Ohm. USDA, ARS, Grain Marketing and Production Research Center, Manhattan, KS 66502.

Wheat Quality Council flour samples from 1996 to 1998 that included 73 winter and 81 spring wheats were baked by a pup straight-dough (S-D) method and a pound sponge and dough (Sp&D) method. The mean values of water absorption (WA) were 66.9% for pup S-D and 59.9% for pound Sp&D. The mix time (MT) of pup S-D and pound Sp&D were 5.5 and 5.3 min, respectively. Mean loaf volumes (LV) were 966 cc for pup S-D and 2406 cc for pound Sp&D. A mean LV per 100 g flour was 797 cc for pound Sp&D. The mean crumb grain scores (CGS) were 3.9 for both baking methods. The differences between mean values of pup S-D and pound Sp&P were significant in WA and LV per 100 g flour but not significant in MT and CGS (P < 5%). Pup S-D showed a higher coefficient of variation (CV) in MT (36%) than that of pound Sp&D (25%). Pound Sp&D CV in WA (10%) was higher than that of pup S-D (4%). Significant (P < 0.1%) correlation coefficients (r) occurred between the two baking methods for WA (r = 0.53), MT (r = 0.53), LV (r = 0.54), and CGS (r = 0.59). Flour protein contents were significantly correlated with WA (r = 0.57, P < 0.1%), MT (r = 0.26, P < 1%), and LV (r = 0.82, P < 0.1%) in a pup S-D. But lower r values occurred between protein content and WA (r = 0.32, P < 0.1%), MT (r = 0.13, P < 16%), and LV (r = 0.54, P < 0.1%) in a pound Sp&D. These results suggested that pup S-D would be better than pound Sp&D in breeding programs, not only due to smaller flour quantity requirement but also more sensitive responses to protein content.