Some effects of gamma radiation on Washington Navel and Valencia oranges

Abstract

Washington Navel and Valencia oranges were irradiated using gamma radiation from Co-60 at doses up to 200 kilorads. Doses below 100 kilorads had only slight effects on the taste of the oranges, ascorbic acid and soluble solids content, and acidity. However, the rinds were frequently damaged by radiation. The effects on the severity of the damage of variety, picking date, dose, temperature of the fruit at irradiation, storage temperature, and period between harvest and irradiation were studied. The conclusions were that radiation is satisfactory for disinfestation of fruit fly where the dose is expected to be about five kilorads, but is unsatisfactory for mould control because of the risk of injury from the higher dose required. Washington Navels picked and irradiated at the start of the harvesting season were found to be particularly susceptible to injury.