antimicrobial, physicochemical, mechanical, and barrier properties of tapioca starch films incorporated with eucalyptus extract

starch is found in abundance in nature and it is one of the raw materials used for food packaging because of the low price, biodegradability, good mechanical and barrier properties. the recycling ability of coating materials was significantly increased by using edible films and coating in comparison to traditional packaging 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 casting method with addition of eucalyptus extract and a mixture of sorbitol/glycerol (weight ratio of 3 to 1) as plasticizers. 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 water absorption capacity (wac), water vapor permeability (wvp) and mechanical properties of the films were evaluated. results showed that by increasing the concentration of eucalyptus extract, tensile strength was increased from 20.60 to 15.68 (mpa), also elongation was increased from 19.31 to 23.57 (%) at break and young’s modulus was decreased from 800.31 to 500.32 (mpa). also incorporation of eucalyptus extract in the structure of biopolymer increased permeability of water vapor of starch films. tapioca starch films incorporated 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 in food packaging.