Hydrothermal treatments of rice starch for improvement of rice noodle quality

Two types of hydrothermal treated rice starches were prepared by annealing and heat-moisture treatment (HMT). Annealing of starch slurry was conducted at 55 °C for 24 h and HMT was applied in starch with 20 g/100 g moisture at 110 °C for 1.5 h, based on the optimization of the treatment conditions. The apparent changes on gelatinization, swelling, RVA paste viscosities and gel hardness of starch were observed. The study on 50% substitution of rice flour with untreated (UR), annealed (AR) or heat-moisture treated (HR) rice starches proved that the cooking and texture quality of rice noodle was substantially affected by the treatments. The composite noodles of flour and hydrothermal treated rice starches exhibited quality parameters which were closer to those of commercial noodles. The results revealed the possibility of utilizing these starches with low quality rice flour so as to produce noodles of acceptable quality. The study also inferred that characterization of RVA paste viscosities and gel texture of flour could become a practical method for predicting the quality of the derived noodle.