In this study, we aimed to elucidate the optimal conditions for baking gluten-free rice bread while considering the powder characteristics of 10 rice flour varieties by optimizing the quantity of water to be added and examining the effects of particle size, protein content, amylose content, and degree of starch damage in rice flour.
Rice breads were prepared with varying quantities of water, and the range of quantity of water that allowed baking varied depending on the variety of rice flour used. We determined that high protein content in rice flour allowed a wide range of quantity of water that can be added to be suitable for bread baking; however, concurrent with this are that the compressive stress of the bread increases as well. Moreover, we examined the effect of ingredient composition on the optimal quantity of water added to ensure the swelling of the rice flour bread and found that the quantity of water that can be added ranged from 15- to 17-fold when the quantity of water to be added was based on the protein content in rice flour. These results indicate that when preparing gluten-free rice bread with a large specific volume, the quantity of water to be added can be determined using the protein content in rice flour as an indicator. Additionally, we found that when the protein content in rice flour is not known, the quantity of water to be added can be adjusted to achieve 10 to 20 Pa loss modulus G’’ of the batter.