Impact of granite irradiation on aflatoxin reduction in pistachio

In this research with the effect of radioactive granite gamma radiation, the reduction of aflatoxin B1 in pistachios was examined in three steps. In the first step, the aflatoxin reduction in small packets by granite bed was tested. In this step, the aflatoxin level of 300 g pistachios packets was reduced up to 81.3 ± 1.5 percent by 4 kg granite bed after 4 days. After observation of aflatoxin reduction by granite bed, the second step was done with increasing the granite and pistachio mass and irradiation time. In this step, the aflatoxin level of 1 kg pistachios was reduced up to 4949 ± 2.6 percent by 6 kg granite after 9 days. According to the results, the aflatoxin reduction of 1 kg pistachios by 1 kg granite after 1 days (as aflatoxin Reduction Coefficient (ARC)) was calculated as ARC = 0.0090 ± 0.0025 (kg. day)^-1. The aflatoxin types of detected in this research were B1 and B2 types that AFB2 level was much less than one. Therefore the effect of granite irradiation on AFB2 reduction wasn't considered. The final step was designed for testing the aflatoxin Reduction Coefficient (ARC). This step was shown that the confidence level between practical result and aflatoxin Reduction Coefficient (ARC) result is about 97 percent. The results indicated that the level of fat and protein of pistachios by granite gamma radiation did not change after 9 days. Therefore the granite irradiation can be used for aflatoxin reduction of pistachios.