Response surface methodology-based preparation of sago starch bioplastic film for food packaging

The increase in the use of plastics during the past few decades has caused environmental pollution due to the non-biodegradable and recalcitrance nature of the plastics. This has caused great problems for the solid waste management efforts. The development of biodegradable polymers from natural and renewable ingredients can address the challenges caused by plastic pollution. The present work deals with the optimization of the preparation process of sago starch-based biodegradable bioplastic films. The sago starch, glycerol-sorbitol mixture, and chitosan were used as polysaccharides, plasticizers, and antimicrobial agents, respectively. The factors screening and design optimization were performed using response surface methodology and Box-Behnken Design to investigate the interactions between all components in the film preparation. Furthermore, the developed bioplastic films were characterized through field emission scanning electron microscopy and Fourier transform infrared spectroscopy. The antimicrobial susceptibility assay showed the inhibition of the growth of Bacillus pumilus and Alcaligenes faecalis XF1 by incorporation of cinnamon essential oil into the film. Moreover, the developed films successfully reduced the proliferation of fungal growth on packaged bread samples. The microbial analysis found that the shelf life of the wheat bread was improved from 3 to 15 days. The sago starch bioplastic films developed in this study can potentially meet the requirements for food packaging films.