茶多酚@沸石咪唑酯骨架材料/壳聚糖/海藻酸钠活性包装膜的制备及表征

本实验以海藻酸钠（sodium alginate，SA）和壳聚糖（chitosan，CS）为成膜基材，并以不同添加量（分别为0%（质量分数，后同）、1%、2.5%、5%）茶多酚（tea polyphenols，TP）@沸石咪唑酯骨架材料（zeolitic imidazolate framework-8，ZIF-8）纳米复合材料为功能性成分，通过层层组装的方式制备TP@ZIF-8/CS/SA复合膜。利用场发射扫描电子显微镜、热重分析仪、差示扫描量热仪、傅里叶红外光谱仪、质构仪、色差仪等对复合膜的形貌、组成进行表征。结果表明，TP@ZIF-8纳米复合材料添加量为5%时改变了CS/SA复合膜的颜色，并且影响了复合膜的微观形态，还增强了复合膜的热稳定性、阻隔性能和机械性能。此外，TP@ZIF-8纳米复合材料的加入使该复合膜表现出良好的抗氧化和抑菌效果。综上，本实验制备出一种具有抗菌和抗氧化的生物可降解活性包装膜，该活性包装膜在食品保鲜领域具有良好的应用前景。

Preparation and Characterization of Tea Polyphenols @ Zeolitic Imidazolate Framework-8/Chitosan/Sodium Alginate Active Packaging Film

Using sodium alginate (SA) and chitosan (CS) as film-forming substrates and different concentrations (0%, 1%, 2.5% and 5%) of tea polyphenol (TP) @ zeolitic imidazolate framework-8 (ZIF-8) nanocomposites as a functional component, TP@ZIF-8/CS/SA composite membranes were prepared by layer-by-layer self-assembly. The morphology and composition of the composite films were characterized by scanning electron microscopy (SEM), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), Fourier transform infrared (FT-IR) spectroscopy, texture analyzer and color different meter. The results showed that addition of TP@ZIF-8 nanomaterial at 5% changed the color, affected the microstructure, and enhanced the thermal stability, barrier performance, and mechanical properties of the composite films. In addition, addition of TP@ZIF-8 nano-composite imparted good antioxidant and antibacterial activity the composite films. Thus, the biodegradable composite active packaging films have good prospects for application in the field of food preservation.