Compositional Changes during Papaya Fruit Ripening

Abstract

The objective of this study was to investigate compositional
changes during ripening of ‘Baladi’, ‘Ekostika I’ and ‘Ekostika II’
papaya fruit cultivars at 20 ±1 ⁰C and 85% - 90% relative humidity. The
fruits of the three cultivars exhibited a typical climacteric pattern of
respiration with peak of respiration of 82, 92 and 98 mg CO 2 / kg-hr,
reached after 10 days in the three cultivars, respectively. Weight loss,
total soluble solids (TSS), total sugars and ascorbic acid content
progressively increased during ripening of the three papaya cultivars.
More increase in TSS and total sugars was observed after the climacteric
peak of respiration. Fruit tissue firmness and total phenolic compounds
decreased continuously during ripening in the three cultivars. Reducing
sugars, total protein and titratable acidity steadily increased to reach a
peak, which coincided with the climacteric peak of respiration, and
subsequently decreased afterwards. The local ‘Baladi’ cultivar had a
lower respiration rate, more firm and less weight loss during ripening,
which may indicate a longer shelf-life than the other two introduced
cultivars. On the other hand, the introduced cultivars were higher in
TSS, total and reducing sugars and ascorbic acid content and lower in
titratable acidity and phenolic compounds, which may reflect a better
eating quality.