Effect of Gelatinized Rice Flour Ration in the Dough on the Physical Properties of Rice Noodles

Abstract

The purpose of this study was to improve the quality of rice noodles by adjusting the gelatinized rice flour ratio in the dough. Two types of rice, Japanese Yumetoiro and Chinese Zhongzao 22 hao (Indica), were used. The color and physical properties such as maximum tensile stress, maximum tensile strain, and the time dependence of dynamic viscoelasticity of cooked rice noodles as well as the micro-structures of the cooked rice noodles were investigated. The lightness of the cooked rice noodles showed no significant differences with the different gelatinized ratios, whereas the yellowness developed with increased gelatinized ratio in the dough. On the other hand, the maximum tensile stress and maximum tensile strain of the cooked rice noodles increased significantly with increased gelatinized ratio. Storage moduli (G') and loss moduli (G'') of the cooked rice noodles also increased significantly with an increase in gelatinized ratio. The retrogradation of cooked rice noodles with higher gelatinized ratio was earlier, and the noodles hardened more easily. Finally, the cooked rice noodles with higher gelatinized ratio showed a more compact microstructure and smaller holes were observed by scanning electron microscopy (SEM) .