RESPIRATION OF GAMMA-IRRADIATED FRESH FRUITS

SUMMARY —The effects of ionizing irradiation with gamma rays on respiration of fresh fruits of avocado, sour sop, mango, yellow passion fruit and papaya were investigated. Respiratory response of these fruits, irradiated in the preclimacteric stage, is characterized by an initial increase in CO₂ liberation followed by a decrease prior to the onset of the climacteric rise associated with ripening. An inverse relationship between the magnitude of the initial increase in respiration and the degree of tolerance to irradiation is indicated, e.g., the avocados, the least tolerant of the fruits investigated, exhibits the greatest initial increase in respiration, and the papayas, the most tolerant, produce the smallest initial increase in respiration. The five fruits studied may thusly be categorized in order of increasing tolerance to irradiation: avocados, sour sop, mangoes, yellow passion fruit and papayas. This category also represents a decreasing order of magnitude of the initial increase in respiration due to irradiation.