In situ formed active and intelligent bacterial cellulose/cotton fiber composite containing curcumin

A novel solid bacterial cellulose/cotton fibers (BCF) composite with a sandwich-like structure as active and intelligent food packaging was formed in situ. BCF or bacterial cellulose (BC) films were vacuum dried and different concentrations of curcumin were absorbed in the films. Scanning electron microscopy showed cotton fibers were combined with BC, and formed a sandwich-like structure. The elongation at break, water solubility, swelling degree, thermal stability, UV barrier property and antioxidant property of films were increased with the cotton fibers in the films. For studying the interaction between solid support and curcumin, Fourier-transform infrared spectroscopy and X-ray diffraction spectroscopy were conducted. Curcumin was successfully doped into solid support films. With the addition of curcumin, the water solubility, tensile strength and swelling degree of films decreased, while elongation at break, thermal stability and UV barrier property increased. When the concentration of curcumin was the same, BCF based films presented improved antioxidant property and more visible color changes than BC based films. The BCF-curcumin films exhibited a color change from bright yellow to brownness with pH variations ranging from 7 to 10. These results indicated that BCF-curcumin films have the ability to be utilized as an active and intelligent food packaging.