Eco-safe composite edible coating of hydrocolloids with papaya leaf extract improves postharvest quality and shelf life of papaya fruit under ambient storage.

Papaya postharvest management using low-temperature storage is discouraged as it is a tropical fruit. Extensive research is going on to preserve papaya quality at ambient storage using edible coatings and its composites. The present investigation examined the effects of an eco-safe composite edible coating consisting of hydrocolloid carboxymethyl cellulose (CMC) (1%), guar gum (1.5%), xanthan gum (0.3%), and Gum Arabic (10%) combined with papaya leaf extract (PLE) (1:1 ratio by volume) applied as dip treatment on "Red Lady" papaya fruit at ambient storage condition. Among all the attempted treatments, "PLE incorporated with CMC (1%)" was found to be the best, as the treated fruit exhibited the highest levels of biochemicals, whereas the lowest levels of physiological and enzymatic activity, which positively affected the shelf life. The "CMC + PLE" treatment enhanced the fruit gloss score by 70.1%, phenolics by 6.1%, ascorbic acid by 22.3%, total carotenoid content by 7.4%, and fruit predilection score by 22.0% over the control fruit. However, it lowered (controlling) the physiological loss in weight by 51.0%, decay incidence by 66.6%, and polygalacturonase and pectin methylesterase activity by 24.92% and 35.29%, respectively, over control. Moreover, this treatment exhibited the highest fruit purchase predilection score and prolonged the storage life for >3 days on the physiological loss standard basis (≤10%). This study indicates that "CMC (1%) with PLE (1:1)" composite coating application on papaya under ambient conditions might be an effective, environmentally friendly, and health-friendly way to retain the quality and extend the storage life.

Evaluation of enzyme treatment conditions on extraction of anthocyanins from Prunus nepalensis L.

The study was designed to investigate the effect of enzyme assisted extraction of anthocyanins from Sohiong fruit (Prunus nepalensis) under varied time, temperature and treatment conditions. Highest anthocyanins yield was obtained by coupling enzymatic treatment along with solvent extraction simultaneously. Additionally, effect of enzyme type, enzyme concentration, reaction time and temperature were evaluated subsequently in following experiments. Cellulase treatment (10% E/S) for 180min at 4°C exhibited highest yield of 984.40±3.84mg C3G/100gdm which accounts to 14.61% higher yield when compared to conventional method (858.84±6.88mg C3G/100gdm). The study provides an economical alternative for commercial extraction of anthocyanins from Sohiong fruit which can be used as a colourant for various food and other products and owing to its antioxidizing properties can be effective for the prevention and treatment of diseases.