Effect of green tea polyphenols on properties of potato starch-chitosan composite film

In order to develop a new active antioxidant packaging material, the effects of green tea polyphenols ( GTP) on the physical, antioxidant and structural properties of the potato starch-chitosan based films were investigated. The results showed that DPPH radical scavenging rate of composite films were enhanced significantly with the addition of GTP, and DPPH radical scavenging rate achieved 94.48% with 2% GTP treatment in 3 min.The addition of green tea polyphenols also decreased water vapor permeability of composite films. However, green tea polyphenols increased the red and yellow color, water solubility, whereas caused the decrease of film flexibility. The changes in physical properties were attributed to the hydroxyl interaction between chitosan-starch and green tea polyphenols according to the FTIR.The results showed that the addition of 0.5% green tea polyphenols could not only improve the antioxidant quality of films, but also have better flexibility.