Effects of electron beam irradiation on the quality of star apple fruits (Chrysophyllum cainito)

Irradiated star apples at the minimum absorbed dose of 400 Gy for phytosanitary purpose in Vietnam have been already approved to import to US. In this study, the fresh star apples were treated with electron beams at doses of 0.4, 0.6, 0.8 and 1.0 kGy to evaluate its effect on quality of fruits. The results showed that electron beam radiation doses of 0.4 kGy and 0.6 kGy did not affect to the surface color and percentage of weight loss of fruits. There was significant difference in overall acceptability score with the values of 3.95, 3.92 and 2.45 between irradiated fruits at 0.4, 0.6 kGy and the control (0 kGy) respectively after 6 days in storage at the ambient conditions (temperature of 26 +/- 1oC and humidity of 85-90%). Thus, dose range between 0.4 and 0.6 kGy should be used to extend the shelf life of star apple fruits. Because of the low penetration depth of electron beams onto products, dose uniformity ratio (DUR) in the standard carton box for packaging the star apple fruits as well as absorbed doses outside and inside of fruits were calculated.