Influence of some post-harvest treatments on guava fruits

Abstract

Guava (Psidium juajava L.) is highly perishable, susceptible to mechanical damage and chilling injury and has a limited postharvest shelf life. This study explored the use of some postharvest treatments to extend the marketable shelf life of guava and to alleviate some pathogenic disorders. Mature yellowish-green guava fruits cv. were treated with hot water, hydrogen peroxide (H 2 O 2 ), calcium chloride grass oil fumigation and various combination between them and then stored at 81C with 90% relative humidity (RH) for 15 days. Fruits were transferred to room conditions at (222C and 55-60 %RH) till the end of the fruit marketable period. Fruits of all treatments showed lower fruit weight loss, decayed fruits and long marketable-life period in comparison to untreated (water only). Calcium chloride + lemon grass fumigation treatment gave fruits with high quality than other treated fruits. Ascorbic acid and total pectin values were the highest with calcium chloride + lemon grass fumigation treatment than in the control and other treated fruits, whereas acid % and SSC values were the lowest. All tested treatments greatly reduced rhizopus rot infection value after 10 days at 81C, rot infection percent was 100% in control fruit, whereas very little infection value was observed in treated fruit. Fruits treated with Calcium chloride + lemon grass fumigation were completely rhizopus rot free through 15 days storage at 81C. The sensory evaluation showed that this treatment could maintain appearance considered the most benefit fruit appearance ,physical, chemical fruit properties and free from rots at 81C for two weeks. This treatment considered the most benefit tested one.