Physiological and quality changes during postharvest ripening of purple passion fruit (Passiflora edulis Sims)

Introduction. Postharvest physiology and ripening in passion fruit are not well documented, which is an impediment in designing handling and storage regimes. Materials and methods. Passion fruits harvested at four different maturity stages were studied for postharvest ripening behaviour and to determine the correct stage of harvesting. Results and discussion. The respiratory climacteric peak was attained in all stages irrespective of harvest maturity, while the ethylene evolution rate increased by almost 8.15 times the initial value to peak levels of 505.35 mu L C2H4.kg(-1.)h(-1) in fruits harvested at the 50% colour turning stage. Changes in Hunter L*a*b* values indicated development of optimum colour only in fruits harvested after 50% colour turning. Fruit quality attributes were also better in fruits harvested after half (50%) colour turning than fruits harvested earlier. Conclusion. Passion fruit should be harvested only after 50% of fruit surface colour has developed, so as to allow for optimum postharvest storage, proper ripening, and development of characteristic flavour and fruit quality attributes.