Study on the effect of tea polyphenol on properties of gelatin-calcium carbonate composite films

In order to develop gelatin- calcium carbonate composite films with antioxidant activity, the different concentrations of tea polyphenol was added to it.The effects of TP concentrations in the film- forming solution on the film properties were determined by measuring thickness, gel strength, tensile strength ( TS) , elongation at break ( EAB) , water solubility ( WS) , water vapor permeability ( WVP) , color, light transmission and transparency, antioxidant activity as well as atomic force microscopy ( AFM) . The results showed that the incorporation of tea polyphenol caused interactions between gelatin and tea polyphenol and gave rise to the films darker appearance, the films showed decreased water solubility and water vapor permeability.After the addition of tea polyphenol, the films showed increased thickness, mechanical properties.Meanwhile, the incorporation of tea polyphenol enhanced2, 2-diphenyl-1-picrylhydrazyl ( DPPH) free radical scavenging activity of the films.The preservation experiment of chilled fresh pork showed the benefits of incorporation of TP into gelatin-calcium carbonate composite film and the potential for using the developed film as an active packaging.