Submitted to: Stewart Postharvest Review
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/26/2015
Publication Date: 9/1/2015
Citation: Wall, M.M. 2015. Phytosanitary irradiation and fresh fruit quality: Cultivar and maturity effects. Stewart Postharvest Review. 11(3):1-6.
Interpretive Summary: Irradiation is an effective quarantine treatment for global trade of fresh produce. The quality and ripening of diverse fruit cultivars can affect sensitivity to radiation treatment, and ultimately consumer acceptance. This report examines the impact of various crop cultivars and maturity stages on the tolerance of fresh fruits to irradiation for the purposes of quarantine security.
Technical Abstract: Irradiation is an effective quarantine treatment for global trade of fresh produce. Variation in cultivars and maturity stages can impact the tolerance of fresh fruits to irradiation for the purposes of quarantine security. Tolerance thresholds for irradiated fruit are lacking for a large number of modern cultivars. Cultivar differences in radiation sensitivity are most apparent for bananas, citrus, peaches and mangoes. Some of the variation attributed to cultivars may be maturity effects. For climacteric fruit, maturity stage at the time of treatment impacts the quality and shelf-life of irradiated product. Irradiation applied at the preclimacteric stage may delay ripening, but higher doses can injure less mature fruit. Overall, many fruit types tolerate doses below 500-600 Gy. The major cultivars in current production should be evaluated at varying stages of maturity following irradiation at the range of doses (> 1000 Gy) approved for quarantine treatment. Respiration and ethylene production rates should be monitored for individual varieties of climacteric fruits, before and after irradiation, to properly gauge the physiological maturity of the fruits and the impact of radiation on fruit ripening. Simulated shipping and ripening conditions following treatment at commercial radiation facilities would provide a clear assessment of the potential for successful export of irradiated fresh fruit.