Film Property Enhancement of Bacterial Nanocellulose Suspension Using High-Pressure Homogenization Parameters

Bacterial nanocellulose (BNC) is a natural polymer gel with unique properties that are suitable for developing advanced film applications such as edible coating and packaging. However, transforming BNC gel into a suspension and applying it as a film still lacks knowledge of the condition and method since BNC film performance depends on many parameters caused by the transformation process. This work studied two important primary variables, the number of homogenization cycles and the BNC concentrations, for transforming BNC gel into aqueous suspension using a microfluidizer to homogenize nanofibers and water medium. The BNC films obtained from the suspensions were examined for their properties, i.e., morphology, crystallinity index, optical, thermal, and mechanical properties. The results explored that the number of homogenization cycles had a non-significant impact on the characteristics and properties of BNC suspension and film. A significant improvement in film properties was found when using a higher BNC concentration at 1% w/v compared with 0.5% w/v at the equivalent number of homogenization cycles (40 cycles). The degradation temperature of this film increased by 13%, and Young’s modulus and tensile strength increased more than twice compared with the 0.5% w/v sample, increasing from 0.3 to 0.7 MPa and from 9 to 19 kPa, respectively. This finding would benefit the further development of BNC film for coating and packaging applications.