Rice husk fiber-reinforced starch antimicrobial biocomposite film for active food packaging

Active packaging with antimicrobial properties has the potential to impede the growth of bacteria and extend the storage life of packaged food items. Corn starch (CS) presents an excellent alternative to conventional packaging materials. However, its usage is limited due to its high hydrophilicity and low mechanical properties. Herein, rice husk fiber (RHF), an agricultural waste, was used as reinforcement, and benzalkonium chloride (BKC) was used as an antimicrobial agent to develop a sustainable and biodegradable packaging film exhibiting antimicrobial properties. The content of RHF varied between 10% and 50%, while the concentration of BKC ranged from 0.05% to 0.2%. The impact of these variations on the mechanical properties, thermal properties, moisture content, surface morphology, biodegradability, and optical properties of the biocomposite film (RHF/BKC/CS) was evaluated and analyzed. At 20% fiber content and 0.05% BKC content, the biocomposite film showed 61% improvement in tensile strength, optimum moisture content, transparency, and water solubility. Also, BKC content was optimized to attain good antimicrobial properties against food-spoiling bacteria. The biocomposite film was found to increase the shelf life of packaged strawberries by more than 11 days. The biocomposite film with excellent properties could be used as a potential packaging material in food, cosmetics, and pharmaceutical industries.