Starting with having Three types of peanut butter, A, B, and C and then placed 25g per each type of peanut butter into sterile stomacher bag. Next, added inocula to the sample and gave it a hand massage for 1 minute to make sure that the culture spread all over the area. Then spread into a thin layer and let it dry for 30 minute inside a biosafety hood until the water activity of the sample equaled to the non-inoculated sample///// After that, the sample bags were sealed and placed into a larger SealPAK bag. The bags were then packed in plastic containers and stored at 25 °C until transportation to the irradiation with 3 dose in 1 Kgy ,2KGy and 3KGy