Development of Active Zein/Alginate Edible Films Incorporated with Cinnamon Essential Oil for Food Packaging Applications

Abstract

The development of biodegradable active packaging materials has attracted considerable attention as a sustainable alternative to petroleum-based plastics. In this study, edible films based on zein and sodium alginate were developed and incorporated with cinnamon essential oil (CEO) to enhance their functional properties for food packaging applications. Different zein-to-alginate ratios were investigated, and ZA2 was identified as the optimal formulation due to its balanced mechanical and moisture barrier properties, exhibiting a tensile strength of approximately 1.8 MPa, an elongation at break of 122%, and a water vapor permeability of 1.10 × 10−10 g m−1 s−1 Pa−1. FTIR analysis revealed interactions among zein, alginate, and CEO, while SEM observations revealed morphological changes associated with the incorporation of CEO into the composite film matrix. The antioxidant activity increased with CEO concentration, reaching a DPPH radical scavenging activity of 32.41% for CEO15. Furthermore, CEO15 exhibited noticeable antibacterial activity against both Escherichia coli and Staphylococcus aureus. Strawberry preservation tests demonstrated that CEO15-coated samples maintained better appearance and freshness than the control and ZA2 samples after 5 days of storage at room temperature. These findings suggest that CEO-loaded zein/alginate films have strong potential as active packaging materials for extending the shelf life of fresh fruits.