ANTIBACTERIAL, ANTIOXIDANT AND OPTICAL PROPERTIES OF EDIBLE STARCH-CHITOSAN COMPOSITE FILM CONTAINING POMEGRANATE PEEL EXTRACT

Biocompatible packaging based on edible films containing active agents used in food to improve quality, extending product shelf life and reducing the risk of pathogen growth. The objective of this study was to prepare composite films from chitosan and starch containing 0, 0.5, 1 and 2% pomegranate pell extract (PPE) and to evaluate their antimicrobial, antioxidant and optical properties and film solubility.

Composite films containing 0, 0.5, 1 and 2% PPE, were obtained by casting method. The film properties were determined by measuring total polyphenolic content, antioxidant activity, optical properties and solubility in water. Agar diffusion method was used for antimicrobial evaluation. All experiments were performed at least in triplicate and collected data was analyzed by ANOVA and Duncan's test using SPSS software.

The edible films containing PPE exhibited more effective impact on the growth reduction of L.monocytogenes than S.aureus and E.coli (p < 0.05). Antioxidant activity and total phenol(TP) of chitosan- starch films was significant increased with the addition of PPE but concentration of 0.5% and 1% in antioxidant activity and 0 % and 0.5% in TP were not significantly different (p<0.05). The color was affected by the addition of PPE; the results showed that increasing PPE yielded lower transparency, darker and more red-yellowish of resulted films. Results also showed that the water solubility of films tended to increase as the level of PPE increases (p<0.05).

This study showed that starch-chitosan composite films containing pomegranate peel extract was significantly antibacterial properties, while shows the higher antioxidant effect. PPE also improves the same physical properties of the film. This edible film has potential for use in extending the shelf life of food products.