Effect of Oregano Essential Oil Content on Properties of Green Biocomposites Based on Cassava Starch and Sugarcane Bagasse for Bioactive Packaging

In this study, 10 wt% sugarcane bagasse fiber-reinforced starch foam composites were prepared with different oregano essential oil (OEO) contents in the range of 2–8 wt% to improve the antimicrobial effectiveness of bioactive packaging. FT-IR analysis confirms that OEO penetrates into starch foam composite. From the result of antimicrobial activity, the incorporation of 8 wt% OEO in starch foam composite achieves the minimum inhibitory concentration against Escherichia-coli (E. coli) and Staphylococcus-aureus (S. aureus). OEO is more effective against S. aureus (Gram-positive bacteria) than E. coli (Gram-negative bacteria). The water absorption capacity and hygroscopicity of foam composite decrease with increasing OEO content. The lowest monolayer value is observed in starch foam composite containing 8 wt% OEO. The soil biodegradation rate and flexural strength of samples slightly decrease with increasing OEO content. As a result, starch foam composite containing OEO can be applied as bioactive packaging to preserve foods.