2013 Volume 82 Issue 1 Pages 49-55
The hard spring wheat cultivars “Harukirari” and “Haruyokoi” were cultivated at the Kamikawa Agricultural Experiment Station, Hokkaido, for 3 years and their grain protein content, wheat ash content, flour protein content, flour ash content, ratio of break flour to middling flour (BM), dough water absorption, gluten index, and loaf volume were evaluated. The flour sifted from “Harukirari” had lower protein and ash contents than the flour sifted from “Haruyokoi”. BM increased with the increase in the grain protein content, and was higher in “Harukirari” than in “Haruyokoi”. As the flour protein content increased, dough water absorption and loaf volume increased, while the gluten index decreased. Dough water absorption and gluten index were lower in “Harukirari” than in “Haruyokoi”, and loaf volume was larger in “Harukirari” than in “Haruyokoi”, while the flour protein content was similar. Size-exclusion high-performance liquid chromatography revealed that the extractable polymeric protein content (EPP), extractable monomeric protein content (EMP), and unextractable monomeric protein content were positively correlated with the flour protein content. EMP, which mainly consists of gliadins, increased with the increase in flour protein content. When the flour protein content was the same, EPP and EMP were higher in “Harukirari” than in “Haruyokoi”. However, the unextractable polymeric protein content was lower in “Harukirari” than in “Haruyokoi”.
