Study on rapid detection of irradiated rice based on RVA profile

In order to confirm whether the rice sample was exposed to gamma radiation,the changes in starch pasting viscosity of rice irradiated by different absorbed doses with additive acid solution and distilled water were investigated.The peak viscosity of irradiated rice sample was significantly decreased with the increment of absorbed doses even for the samples stored over 360 days.Irradiation samples can be distinguished from non-irradiated samples by their RVA profile as in the acid solution(pH=2.5),the starch pasting viscosities of irradiated rice samples were apparently higher while the starch pasting viscosities of non-irradiated rice samples were lower than that in distilled water(pH=7.0).The irradiation absorbed dose can be estimated accurately by the regression equation constructed with peak viscosity and absorbed doses.