cooking qualities of rice

To further consummate and improve the theory about application of ionizing irradiation disinfection and sterilization to stored-grain, rice samples were exposed to electron beam with dosage levels of 0, 0.83, 1.56, 2.30, 4.93 kGy to evaluate the effect of electron beam irradiation on nutritive quality, pasting property, cooking and eating qualities of rice. The results showed that the protein content and amino acid composition of rice were not significantly influenced by irradiation (p>0.05), fatty acid value and gel consistency raised while water absorption and swelling degree reduced with the increasing irradiation dosage (p<0.05). No significant change in pasting temperature was observed between irradiated and non-irradiated samples (p<0.05), but peak viscosity, breakdown, setback of rapid visco analyzer were significantly decreased with dosage increasing (p<0.05). The cooking quality was significatnly lowered by irradiation with the increasing dosage (p<0.05), and the cooked rice browned at 4.93 kGy dosage level. Thus, the adequate electron beam irradiation dose for rice should be less than 2.30 kGy, and the best qualities of rice will be kept when irradiated with 0.83 kGy. The experimental results can provide a theoretical evidence for the choice of irradiation dosage for the application of low-energy electron beam irradiation in sterilization as well as insect disinfection of rice.