Effect of Postharvest Treatments on Physiological, Chemical, Microbial and Sensory Qualities of Fruits of Papaya Variety Surya

Papaya is a climacteric fruit which is highly perishable due to rapid ripening and softening and susceptibility to biotic or abiotic stresses, resulting in large losses during storage. Traditionally, people resort to the application of synthetic chemical fungicides on to the crop plant and to the fruits during storage, to control the anthracnose caused by the fungus Colletotrichum gloeosporioides on fruits. But their repeated use has caused resistance in microorganisms and toxicity for humans. Hence, nowadays there has been increasing interest in using natural alternatives instead of chemical treatment.

Fruits of papaya variety Surya collected at fully mature green stage were subjected to different postharvest management practices namely precooling, surface sanitization, treatment with chitosan and were packaged in corrugated fibre board boxes and stored till the end of shelf life under ambient condition. Untreated fruits (control) were also used in the study.

Fruits coated with chitosan (1%) registered an improved shelf life of 6.33 days as against 4.33 days in control in ambient storage and it further improved the sensory score for all the organoleptic parameters, after six days of storage. 1% chitosan coating also reported significantly lowest physiological loss in weight (3.51%), ion leakage (60.47%), total soluble solids (12.13°Brix), total carotenoids (2.34 mg 100 g^-1), total sugar (7.26%) and reducing sugar (6.34%) and least disease index (16.67%), bacterial count (22.33 cfu/ml × 10⁶) and fungal count (7.33 cfu/ml × 10³) after three days of storage when compared with control.