Quality improvement of rice noodle restructured with rice protein isolate and transglutaminase

In an effort to improve the properties of rice dough and quality of gluten-free rice noodle, transglutaminase (TGase) and rice protein isolate (RPI) were applied to rice noodle making process. The storage and loss moduli of rice dough increased by TGase treatment, whereas they decreased with RPI supplementation. The combined treatment of RPI + TGase on rice dough fully recovered the reduced moduli caused by RPI only supplementation to control level, and increased most of viscosity parameters of rice noodle in RVA analysis. This additional treatment of TGase also increased development time, and maximum and peak torques of RPI-supplemented rice dough in Mixolab® analysis. Cooking loss and water turbidity of rice noodle decreased by 54.8% and 66.6%, respectively, after TGase + RPI treatment. Scanning electron micrographs showed cracked noodle surface became smoothed with TGase treatment, which was more obvious with RPI + TGase treatment. These results suggest RPI + TGase treatment could improve the quality of rice noodle without the use of gluten-like ingredients.