Biopolymer Research Group, Food Science and Technology Division, Agriculture Department, Damghan Branch, Islamic Azad University, Damghan, Semnan, Iran
Starch is found in abundance in nature and it is one of the raw materials used for food packagingbecause of the low price, biodegradability, good mechanical and barrier properties. The recycling ability ofcoating materials was significantly increased by using edible films and coating in comparison to traditionalpackaging and it could be an alternative for synthetic films. In this research, the effect of eucalyptus extract(Aqueous Extract) was investigated on tapioca starch films. Tapioca starch films were prepared by castingmethod with addition of eucalyptus extract and a mixture of sorbitol/glycerol (weight ratio of 3 to 1) asplasticizers. Eucalyptus extract incorporated to the tapioca starch films were dried at different concentrations(0, 15, 25, and 35 of total solid) under controlled conditions. Physicochemical properties such as waterabsorption capacity (WAC), water vapor permeability (WVP) and mechanical properties of the films wereevaluated. Results showed that by increasing the concentration of eucalyptus extract, tensile strength wasincreased from 20.60 to 15.68 (MPa), also elongation was increased from 19.31 to 23.57 (%) at break andYoungâ€™s modulus was decreased from 800.31 to 500.32 (MPa). Also incorporation of eucalyptus extract in thestructure of biopolymer increased permeability of water vapor of starch films. Tapioca starch filmsincorporated with eucalyptus extract exhibited excellent antimicrobial activity against E. Coli. In summary,eucalyptus extract improves functional properties of tapioca starch films and this types of films can be used infood packaging.