Interactive Effect of Variety and Irradiation Dose on Postharvest Behaviour of Fruits of Two Plantain (&i&Musa&/i& sp AAB) Varieties from the Green Stage to the Onset of Ripening

摘要

Controlling ethylene production and respiratory rate of climacteric fruits is reported to extend the shelf-life of those produce. The aim of this present research was to determine the effect of five (5) doses of gamma irradiation as an ethylene and respiration inhibitor on two (2) distinct varieties of plantain ( Musa sp AAB) up to the onset of ripening. The variety and irradiation dose applied had a significant interaction on the number of days to the onset of fruit ripening. The daily mean ethylene production for both varieties was lowest at 200 Gy. Even though Apantu had a lower daily average as compared to Apem, it reached the onset of ripening relatively quicker than Apem. Irradiation caused a significant decrease in the respiratory rate of the plantains. Irrespective of the dose applied, the unirradiated usually had a significantly higher respiratory rate and the accompanying carbon dioxide production. Plantain varieties irradiated at 1000 Gy had the highest amount of total soluble solids contents (10.7°Brix) significantly higher than the other stages of ripening yet similar to the plantain varieties irradiated at 600 Gy (10.6°Brix), 800 Gy (10.6°Brix) and the unirradiated (0 Gy) plantain varieties (10.3°Brix). The lower levels of soluble solids may confer a better cooking quality as plantains would be less sweet and also less prone to textural breakdown when cooked.