Abstract Cactus pears (Opuntia ficus-indica) are rich in betalains, which are water-soluble nitrogenous pigments. This study aimed to develop antioxidant, antimicrobial and ammonia-sensitive packaging films by adding cactus pears extract (CPE) into quaternary ammonium chitosan (QAC)/polyvinyl alcohol (PVA) blend. The impact of CPE addition on the structure, physical and functional characteristics of the film was determined. Scanning electron microscopy revealed 1 wt% of CPE was compatible with film matrix, resulting in the most uniform and smoothest cross-sectional morphology. Fourier transform infrared and X-ray diffraction analysis demonstrated CPE interacted with film matrix via hydrogen bonding interactions. The addition of 1 wt%, 2 wt% and 3 wt% of CPE greatly enhanced the UV–vis light barrier, elongation-at-break, and antioxidant, antimicrobial and ammonia-sensitive properties of QAC/PVA films. However, only 1 wt% and 2 wt% of CPE addition increased water vapor barrier property and tensile strength of QAC/PVA films. The color of QAC/PVA films containing 2 and 3 wt% of CPE changed from purple to orange when shrimp was not fresh. Our results suggested QAC/PVA films containing CPE could be used as food packing materials in the future.

中文翻译：

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基于季铵壳聚糖、聚乙烯醇和富含甜菜碱的仙人掌梨 (Opuntia ficus-indica) 提取物的抗氧化、抗菌和氨敏感性薄膜的开发

摘要 仙人掌梨（Opuntia ficus-indica）富含甜菜碱，是水溶性含氮色素。本研究旨在通过将仙人掌梨提取物 (CPE) 添加到季铵壳聚糖 (QAC)/聚乙烯醇 (PVA) 混合物中来开发抗氧化、抗菌和氨敏感性包装膜。确定了 CPE 添加对薄膜结构、物理和功能特性的影响。扫描电子显微镜显示 1 wt% 的 CPE 与薄膜基质相容，导致最均匀和最光滑的横截面形态。傅里叶变换红外和 X 射线衍射分析表明 CPE 通过氢键相互作用与薄膜基质相互作用。添加 1 wt%、2 wt% 和 3 wt% CPE 大大增强了 UV-vis 光阻隔、断裂伸长率和抗氧化剂，QAC/PVA 薄膜的抗菌和氨敏感性。然而，仅 1wt% 和 2wt% 的 CPE 添加增加了 QAC/PVA 薄膜的水蒸气阻隔性能和拉伸强度。当虾不新鲜时，含有 2 和 3 wt% CPE 的 QAC/PVA 薄膜的颜色从紫色变为橙色。我们的研究结果表明，含有 CPE 的 QAC/PVA 薄膜在未来可用作食品包装材料。