Extending the Shelf-life of Pear Fruits by Using Gamma Irradiation

The effects of gamma irradiation on lesion diameters of grey mold disease of pear and some physico-chemical parameters of pear fruits were studied in this investigation as a prestorage treatment for extend shelf life of pear fruits. Pear fruits (Pyrus Communis, L.) were exposed to different gamma irradiation doses 0, 0.5, 1, 1.5, 2, 2.5 and 3 KGy and stored for 10, 20 and 30 days in 0 degrees C and 85-90% RH. The increment of irradiant dose caused decrement of lesion diameters of grey mold disease of pear. The narrowest diameters were recorded with 3.0 KGy irradiation dose. The low dose of gamma irradiation 0.5 KGy gave a relatively high value of firmness although in higher doses firmness of pear fruits decreased. The highest loss weight was found in unirradiated fruits while the loss of weight in all irradiated fruits was still lower than those of unirradiated ones and low radiation doses decreased the loss of weight. Total soluble solid increased with increasing in storage periods with respect to gamma irradiation effect there was fluctuation in total soluble solid values. There was a decreasing in acidity during storage of irradiated and un-irradiated fruits. Free amino acid and soluble protein show a slight increasing at 0.5 KGy such increasing was followed by a gradual decrease in higher gamma irradiation doses.