Effect of microwave treatment on RVA spectrum characteristic values and microstructure of rice

Different microwave power and time was to deal with packaged rice, and then quality measurement and scanning electron microscopy (SEM) were made.The changes of rice gelatinization quality and microstructure were analyzed systematically.Moreover, the variation and mechanism of the RVA spectrum characteristic value were dicussed from the point view of microstructure. The results showed that microwave treatment reduced the rice cooking gelatinization peak viscosity, through viscosity, final viscosity and setback. Gelatinization temperature and breakdown values increased with the increase of microwave power and treatment time.Both microwave power (400, 640 W) and treatment time (60, 90 s) had significant effects on the characteristic value of RVA (p < 0.05) , while the power increased to 800 W and time reached to 120 s were both extremely significant (p < 0.01) .Microwave treatment modified the structure and morphology of starch granules, the space of starch granules became larger after microwave treatment, and then more water could be penetrated during cooking, so the quality of rice was improved.Microwave treatment optimized pasting properties of rice, changed the morphology and structure of rice starch granules and improved the eating quality of rice.