Bio-Composite Films from Carrageenan/Starch Reinforced with Nanocellulose for Active Edible Food Packaging: Development and Optimization

Petrochemical plastics are widely used for food protection and preservation; however, they exhibit poor biodegradability, resisting natural degradation through physical, chemical, or enzymatic processes. As a sustainable alternative to conventional plastic packaging, edible films offer effective barriers against moisture, gases, and microbial contamination while being biodegradable, biocompatible, and environmentally friendly. In this study, novel active food packaging materials (in film form) were developed by incorporating starch, carrageenan, nanocellulose (NC), Aloe vera, and hibiscus flower extract. The effects of varying the matrix composition (26.5–73.5 wt.% starch/carrageenan), NC concentration (2.77–17.07 wt.%), and particle type (fibers or crystals) on the film structure and characteristics were analyzed using various methods. Scanning electron microscopy demonstrated good homogeneity and effective dispersion of NC within the blend matrix. An increased carrageenan content in the film improved wettability, moisture absorption, solubility, and water vapor permeability. The mechanical properties of the films were enhanced by NC incorporation and higher carrageenan content. The developed films also exhibited effective UV radiation barriers and biodegradability. Films with low carrageenan content (less than 33.3%) and high NC content (7%, 10% crystals or 10%, 15% fibers) exhibited optimal properties, including enhanced water resistance, hydrophobicity, and mechanical strength, along with reduced water vapor permeability. However, the high water solubility and moisture absorption (above 55% and 14%, respectively) indicated their unsuitability as packaging materials for food products with wet surfaces and high humidity. The results suggest that these films are well suited for use as edible food packaging for fruits and vegetables.