Effect of Molecular Architecture of Rice Starch on the Baking Qualities and Rheological Properties of Pure Rice Bread

Bread can be prepared using only rice flour if the viscoelastic properties of the rice batter are appropriate. These properties depend on the line of rice due to differences in the amylose content and the architecture of the amylopectin between rice lines; consequently, the rheology of rice batter can be changed by using flour made from various rice lines. In the present study, we used the three mutant rice lines, namely, Nipponbare, el, and #4019, which have different amylopectin architectures and different amylose contents. The baking qualities of breads Made from these rice lines were characterized by expansion ratio and bubble size. Cross-sectional images of the baked breads were also examined. For rheological assessment, we measured the storage modulus G' and the loss modulus G '' of batter made using flour from each line. The best baking qualities was obtained using line el. A molecular model of the swelling of amylopectin is presented to explain the storage modulus results.