聚己内酯/蒙脱土/壳聚糖薄膜的制备及其应用

Preparation of Poly(ε-caprolactone)/Montmorillonite/Chitosan Layer Film and Its Application

目的提高聚己内酯(PCL)薄膜对氧气和水蒸气的阻隔性,并应用于冷鲜肉的包装中,以延长冷鲜肉的货架期。方法通过正负电性吸引将带有负电性的蒙脱土混入带有正电性的壳聚糖中,并均匀地涂覆在具有负电性的PCL薄膜表面。分别用氧气透过率分析仪、水蒸气透过率分析仪、质构仪、傅里叶变换红外光谱仪,以及差示量热扫描仪测试复合薄膜的包装特性,并通过测试被包装冷鲜肉的pH值、汁液流失率和菌落总数等指标来确定货架期。结果随着蒙脱土和壳聚糖加入量的增加,复合薄膜的氧气透过率和水蒸气透过率降低,PCL/DK2/CS3的氧气透过率达到222 cm3/(m2·d),水蒸气透过率为22.3 g/(m2·d),断裂伸长率和屈服强度分别为589%和37.22 MPa。结论 PCL复合薄膜将冷鲜肉的保质期延长到23d。

Objective To improve the oxygen and water vapor barrier of poly（ε-caprolactone） （PCL） film, and to extend the shelf life of chilled meat. Methods The PCL layer film was prepared by coating of chitosan and montmorillonite, and the packaging properties were evaluated by tensile test, vapor permeability （WVP） test, oxygen transmittance test, DSC and FTIR. Then, total bacterial count, drip loss and pH of chilled meat were tested during the cold storage to determine the shelf life of chilled meat, which was packaged in PCL layer packing bag. Results With the increase of montmorillonite and chitosan addition, the oxygen transmission rate and water vapor permeability of layer films were reduced, the PCL/DK2/CS3 oxygen transmission rate reached 222 cm3/（m2·d）, and the water vapor transmission was 22.3 g/（m2· d）. The yield strength and elongation at breakage was 589% and 37.22 MPa, respectively. Conclusion The preservation period of chilled meat was extended to 23 days.