目的 制备具有一定力学性能、阻隔性能和抗氧化活性的pH敏感性包装膜。方法 以壳聚糖(CS)为基材，铁皮石斛花色苷(DOA)和紫皮石斛花色苷(DDA)为添加剂，采用溶液共混法制备铁皮石斛花色苷-壳聚糖复合膜(DOA-CS)和紫皮石斛花色苷-壳聚糖复合膜(DDA-CS)。通过扫描电子显微镜和傅里叶变换红外光谱对复合膜进行表征;研究DOA和DDA的质量分数对复合膜的物理性能、力学性能、热稳定性能和抗氧化能力的影响;通过复合膜对不同pH值的颜色响应考察其pH敏感性。结果 DOA和DDA的添加显著改善了壳聚糖膜的力学性能、阻隔性能和热稳定性，特别是当2种花色苷添加量达到10%时，复合膜展现出最优的拉伸强度和较低的水蒸气透过率。在200~300 nm内，复合膜均具有较好的紫外光阻隔能力。复合膜的抗氧化试验显示，添加DOA和DDA能显著提高膜的抗氧化能力，且DOA-CS的抗氧化能力优于DDA-CS的。此外，复合膜还表现出良好的pH敏感性，能够随pH值的变化而改变颜色，这为食品包装提供了潜在的新功能。结论 DOA-CS和DDA-CS复合膜具有良好的应用前景，不仅可以作为食品包装材料，还可以作为食品新鲜度的指示剂。

The work aims to prepare pH-sensitive packaging films with certain mechanical properties, barrier properties, and antioxidant activity. With chitosan (CS) as the base material, and dendrobium officinale anthocyanins (DOA) and dendrobium devonianum anthocyanins (DDA) as additives, the DOA-chitosan composite film (DOA-CS) and DDA-chitosan composite film (DDA-CS) were prepared by the solution blending method. The composite films were characterized by SEM and FTIR. The effects of the mass fractions of DOA and DDA on the physical properties, mechanical properties, thermal stability, and antioxidant capabilities of the composite films were studied. The pH sensitivity of the composite films was examined through their color response to different pH values. The addition of DOA and DDA significantly improved the mechanical properties, barrier properties, and thermal stability of the chitosan films. In particularly, when the anthocyanin content reached 10%, the composite films exhibited optimal tensile strength and lower water vapor permeability. Within the 200-300 nm range, the composite films also showed good UV-blocking capabilities. Antioxidant tests revealed that adding DOA and DDA significantly enhanced the antioxidant capability of the films, with DOA-CS having superior antioxidant properties compared to DDA-CS. Additionally, the composite films displayed good pH sensitivity, capable of changing color with changes in pH, providing potential new functionality for food packaging. The DOA-CS and DDA-CS composite films have promising application prospects, not only as food packaging materials but also as indicators of food freshness.