Radiation processing of fruits and vegetables-a technically and economically feasible technology

Exporting fresh tropical fruits and vegetables to non-infested areas often requires an approved and efficacious quarantine treatment. The feasibility and efficacy of the gamma-radiation process has been demonstrated through quality retention of fresh commodities irradiated at 0.26-0.30 kGy for fruit fly control. Experimental results have shown that papayas and mangoes can be irradiated at up to 1.0 kGy without any adverse effects on their organoleptic and nutrient qualities. Thus it is possible to combine irradiation within this dose level with other techniques to extend the shelf-life of fruits. For example, the shelf-life of papayas can be extended 3-4 days longer after hot water treatment (49 degrees C for 20 minutes for decay control followed by gamma-radiation at 0.75 kGy.) Slowing of the fruit's respiration results in a delay in its ripening. Irradiation at 0.30 to 0.50 kGy preserves the organoleptic qualities of California citrus and stone fruits. Citrus can tolerate higher doses than stone fruits especially if refrigeration follows irradiation. The extension of shelf-life of irradiated onions and potatoes at low dose (0.02 - 0.15 kGy) through sprout inhibition has been established by a number of studies. The prospect of low dose irradiation of fruits and vegetables is good because problems previously existing as barriers to early commercialization of the radiation process are being resolved. These include: government regulations; economic feasibility; and industry interest. Further efforts are needed, however, to develop international trade agreements on irradiated foods and to launch a consumer education program so as to instil confidence and increase consumer acceptance of the safety and benefits of irradiated foods