Physiological and Chemical Changes during Ripening of Costa Rican Bananas Harvested in Different Seasons

Abstract

Mature green `Grande Naine' bananas (Musa AAA) were harvested 13 weeks after flowering in June and Sept. 1993 and Feb. and Mar. 1994 and were sent air freight to Raleigh, N.C. Fruit were held under 1) storage (36 days at 14 C and 80% to 90% relative humidity) or 2) ripening (8 days storage, followed by ethylene treatment on day 8 and subsequent storage at 17 °C and 80% to 90% relative humidity). Despite of similar grade and age, length of the preclimacteric phase (green life) was different between fruit harvested at different times of the year. Fruit harvested in February and March had a longer green life than those harvested in June and September. Rate of respiration best described changes that occurred during the postharvest life of bananas; however, variables such as pulp pH and soluble solids could be commercially useful measures. Once gassed with ethylene, ripening rates were similar between all four lots of fruit, indicating that seasonal variation probably doesn't contribute much to variability seen during ripening. Hand position in the bunch did not have a large influence on variability during ripening or storage.