In the present study, pomegranate peel extract was used as a reinforcing agent in developing chitosan-based edible film. Different concentrations (0.2 g/mL, 0.4 g/mL, 0.6 g/mL, 0.8 g/mL, and 1.0 g/mL) of pomegranate peel extract were incorporated in chitosan-based edible film. A neat chitosan film was used as a control. This work covers the effect of pomegranate peel extract on the physical, biological, mechanical, thermal, and barrier properties of enriched chitosan-based edible film. The results showed that the thickness (0.142–0.159 mm), tensile strength (32.45–35.23 MPa), moisture (11.23–15.28%), opacity (0.039–0.061%), water (1.32–1.60 g·mm/m²), gas barrier properties (93.81–103.45 meq/kg), phenolic content (5.75–32.41 mg/g), and antioxidant activity (23.13–76.54%) of the films increased with increasing volume fraction of pomegranate peel extract. A higher concentration of incorporated pomegranate peel extracts significantly (p < 0.05) reduced the thermal stability of the film, along with its transparency, solubility, swelling, and color. This work revealed that the incorporation of a higher portion of pomegranate peel extract in chitosan film holds significant (p < 0.05) potential for the increase in biological activities of such films in terms of antioxidant and antimicrobial behavior. The properties of pomegranate peel extract-enriched chitosan films could be an excellent cure for free radicals, whereas they could also inhibit the growth of the foodborne pathogens during the processing and preservation of the food. Further studies are needed for the application of pomegranate peel extract-enriched edible films on food products such as fruits and vegetables in order to extend their storage life and improve the quality and safety of preserved food products.

The polysaccharide based composite biomaterial (coating) used in preserving fruits and vegetables during storage is attracting increased attention as it is biodegradable material that prolongs shelf life. In the present investigation, chitosan–pullulan (50:50) composite edible coating was prepared with pomegranate peel extract (0.02 g/mL) as an active antioxidant agent. The effect of treatment with pomegranate peel extract enriched chitosan–pullulan composite edible coating on the shelf life of mango fruits during 18 days of storage period at room (23 °C) and cold (4 °C) temperature was evaluated. Results of the present study demonstrated that the application of chitosan–pullulan composite edible coating significantly (p ≤ 0.05) influences the storage life of mango fruits at both storage temperatures. The chitosan–pullulan composite edible coating reduced the physiological loss in weight (PLW), and maintained total soluble solids (TSS), acidity and pH of coated mango fruits as compared to the control. In addition, fruit sensory quality such as freshness, color, taste and texture were also retained by the treatment. Furthermore, sustained firmness, phenolic content and antioxidant activity confirmed the effectiveness of the pomegranate peel extract enriched chitosan–pullulan composite edible coating on mango fruits. The phenolic, flavonoid and antioxidant activity of coated fruits were retained by pomegranate peel rich edible coating. Therefore, the chitosan–pullulan (50:50) combination with pomegranate peel extract can be used as an alternative preservation method to prolong the shelf life of mango fruits at room and cold storage conditions. However, more in-depth studies are required at farm and transit level without affecting the postharvest quality of mango fruits, providing more revenue for farmers and minimizing postharvest losses.

Fruit by-products are considered as a potent natural source for value-added compounds such as starch, pectin as well as bioactive compounds. These are also rich source for carbohydrate, minerals, vitamins, fibers, phenolic compounds, flavonoid compounds, anthocyanin, hydrolysable and condense tannins. The starch and pectin are natural-based polysaccharide produce also after fruit processing; has unique properties to develop biodegradable packaging and can expand the possible range of uses in food industries. Recently, the consumer and industry demand for the biodegradable and edible packaging has been increased. Edible packaging is considered alternatives of the synthetic polymer and help to enhance the shelf life of the food products while retaining their nutritional, biological and sensory quality. It helps in minimizing lipid oxidation; reducing weight loss, retarded respiration and enzymatic browning of the food products, that is, fruits & vegetables and others. The present review explores about the edible packaging, physiochemical properties and edible film forming ability of fruit wastes of apple, banana peel, citrus, grapes, jack fruit, mango, pomegranate, pineapple, and tamarind. Therefore, the by-products of the fruit processing can be utilized to develop edible coating and film to enhance the shelf life of food products at commercial scale.

An experiment was carried out to investigate the effect of prepared chitosan:pullulan (50:50) blend edible coating enriched with pomegranate peel extract on the quality, sensory attributes and shelf life of litchi fruit cv. Deshi throughout the 18 days storage period at room (23 ± 3ºC, RH- 40-45%) and cold (4 ± 3ºC, RH- 90-95%) temperature. The recorded results revealed that the application of chitosan:pullulan (50:50) blend edible coating exhibited significantly reduce the increasing physiological weight loss, TSS, acidity and browning (color) of litchi fruits during storage as compared to control litchi. Whereas the treated fruit showed lower decreasing weight loss at room (44.49 ± 0.30%) and 4ºC (10.41 ± 0.16%) temperature as compared to control litchi on 18^th days of storage. Increasing TSS & TA, decreasing pH, phenolic, flavonoid and antioxidant activity were control by the treatment of edible coating. The sensory characteristics were recorded higher in treated litchi fruits on 9^th days of storage period at both storage conditions. The results of the sensory evaluation confirmed that the treatment of chitosan:pullulan blend edible coating could be effective to prolong the shelf life of litchi at both storage condition. Paired “t” test was used to the comparison between the control and treated litchi for both room and cold storage. Significance difference (P ≤ 0.05) and correlation was analyzed between the control and coated samples of litchi fruit during the storage period. Further study should be needed to evaluate the effect of chitosan and pullulan blend edible coating on other fruits and vegetables.