Effects of putrescine postharvest dips and refrigerated storage temperature on quality attributes and shelf-life of ‘Solo’ papaya fruit

Purpose: Low temperature storage is commonly used to extend papaya (Carica papaya L.) fruit storability. The optimal recommended storage temperature is below ۱۰ °C for export and distant markets. However, chilling injury (CI) disorder occurs at ۱۰ °C or lower temperatures (۵-۸ °C) during prolonged cold storage. Chilling injury affects fruit quality and consumer preference. Therefore, the study investigated the potential of postharvest polyamine dips to improve the quality and shelf-life of ‘Solo’ papaya fruit. Research Method: Mature papaya fruit were treated with putrescine (PUT) dips (۰, ۱, ۲ or ۳ mM) and stored for ۲۱ days at ۷.۵ °C plus ۶ days at ambient temperature. Findings: The results showed that ۲ and ۳ mM PUT treatment significantly (P<۰.۰۵) reduced mass and firmness loss compared to ۱ mM PUT dips and untreated fruit. The same trend was observed in peel colour change. Furthermore, the results showed that ۲ mM PUT treatment retained lower titratable acid and total soluble solids values compared to control fruit. Research limitations: The study did not focus on Put mode of action including antioxidant system response. Originality/Value: The study demonstrated that ۲ and ۳ mM PUT postharvest dips reduce ‘Solo’ papaya pathological and physiological disorders during low temperature long storage. Therefore, ۲ mM has the potential to improve postharvest quality by reducing the onset/development of pathological and physiological disorders under low temperature storage thereby benefitting exporters.

Keywords:

Carica papaya L , chilling injury , Lower temperature , Physiological disorder , Polyamines