Phenolic and carotenoid profiles of papaya fruit (Carica papaya L.) and their contents under low temperature storage.

BACKGROUND

Tropical fruits are rich in phenolic and carotenoid compounds, and these are associated with cultivar, pre- and postharvest handling factors. The aim of this work was to identify major phenolics and carotenoids in 'Maradol' papaya fruit and to investigate their response to storage temperature.

RESULTS

Ferulic acid, caffeic acid and rutin were identified in 'Maradol' papaya fruit exocarp as the most abundant phenolic compounds, and lycopene, β-cryptoxanthin and β-carotene were identified in mesocarp as the major carotenoids. Ranges of contents of ferulic acid (1.33-1.62 g kg(-1) dry weight), caffeic acid (0.46-0.68 g kg(-1) dw) and rutin (0.10-0.16 g kg(-1) dw) were found in papaya fruit, which tend to decrease during ripening at 25 °C. Lycopene (0.0015 to 0.012 g kg(-1) fresh weight) and β-cryptoxanthin (0.0031 to 0.0080 g kg(-1) fw) were found in fruits stored at 25 °C, which tend to increase during ripening. No significant differences in β-carotene or rutin contents were observed in relation to storage temperature.

CONCLUSION

Phenolics and carotenoids of 'Maradol' papaya were influenced by postharvest storage temperature with exception of β-carotene and rutin. Ripe papaya stored at 25 °C had more carotenoids than those stored at 1 °C. Low (chilling) temperature (1 °C) negatively affected the content of major carotenoids, except β-carotene, but preserved or increased ferulic and caffeic acids levels, as compared to high (safe) temperature (25 °C).