In conclusion, purple passion fruit exhibited
a typical climacteric pattern during postharvest
ripening. Respiration and ethylene production
increased exponentially during
ripening and attained climacteric peaks in
all maturity stages. The ethylene evolution
rate increased by about 8.15 times from the
initial value in stage III. Also, optimum colour
of passion fruit developed only in stage-
III and stage-IV fruits. Notwithstanding loss
in weight and fruit shrivelling, there was
increase in pulp yield. This confirmed that
fruit shrivelling was due to loss of moisture
from the pericarp, while the edible portion
remained unchanged in quantity. Thus,
shrivelling in passion fruit does not necessarily
mean loss of quality or quantity. Fruits
harvested in stage III and stage IV maintained
significantly higher total soluble solids
and lower acidity than those in stage I
and stage II, throughout the storage period.
This explains the development of unripewoody
flavour in fruits harvested before
proper maturity (stage I and stage II), as also
reported by other authors. Also, fruit quality
analysis revealed considerably high bioactive
compounds such as phenolics, ascorbic
acid and carotenoids in stage-III harvested
fruits. We conclude that passion fruit should
be harvested only after fruits have attained
50% colour turning (stage III). This would
assist growers in scheduling harvest for distant
markets or export, so that optimum fruit
quality attributes may be developed by the
time consumers procure them.