Indicator films based on nano-ZnO, purple tomato anthocyanins and polyvinyl alcohol for application in chicken packaging

ranged from 30.54% to 93.82% and from 23.41% to 88.31%, respectively. Moisture content, water vapor transmission rate, thermal stability, and antibacterial activity exhibited gradual improvement, whereas antioxidant capacity and swelling rate decreased from 68.1% to 38.3% and from 127% to 42%, respectively. When applied in chicken breast packaging, composite films with 0% and 5% nano-ZnO showed noticeable color difference changes across different spoilage stages of the chicken breast, indicating their potential as freshness indicator labels.