Recently, chitosan film has been widely used to extend the shelf life of food. In this study, high, medium and low molecular weight of chitosan were used as raw materials to prepare a series of films (C1-C27) by controlling the content of chitosan and glycerol, and their mechanical properties, water vapor permeability (WVP), oxygen transmittance (OP), morphology and antibacterial properties were characterized as well. The results indicated that all films had film-forming properties. Among them, the film C16 with high molecular weight, high chitosan content and 50% glycerol/chitosan (w/w) exhibited the excellent transparency (91.2%), elongation at break (28.948%), tensile strength (77.963 MPa), WVP (1.46 × 10-12gcm/cm2·sPa), smooth morphology, denser structure and antibacterial property (Staphylococcus aureus and Escherichia coli). Meanwhile, the preservation properties of chitosan films were evaluated by strawberry preservation. Almost all the studied films had better preservation effect than the commercially available PE films, especially of which the film C16 was the best compared with others. It maintained the physical and chemical parameters (weight loss ratio, total soluble solids, titratable acidity, total ascorbic acid and color change) of strawberry most obviously. Hence, chitosan films had great potential for the industrial application of fruit preservation.

中文翻译：

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食品包装用三种分子量的壳聚糖薄膜的制备与表征。

最近，壳聚糖膜已被广泛用于延长食品的货架寿命。在这项研究中，以壳聚糖的高，中，低分子量为原料，通过控制壳聚糖和甘油的含量以及它们的机械性能，水蒸气透过率（WVP），制备了一系列薄膜（C1-C27），氧透过率（OP），形态和抗菌性能也进行了表征。结果表明，所有膜均具有成膜性能。其中，具有高分子量，高壳聚糖含量和50％甘油/壳聚糖（w / w）的薄膜C16表现出优异的透明度（91.2％），断裂伸长率（28.948％），拉伸强度（77.963 MPa），WVP （1.46×10-12gcm / cm2·sPa），形态光滑，结构致密，具有抗菌性能（金黄色葡萄球菌和大肠杆菌）。与此同时，通过草莓保存评价壳聚糖膜的保存性能。几乎所有被研究的薄膜都比市售的PE薄膜具有更好的保存效果，尤其是其中的C16薄膜是最好的。它最明显地保持了草莓的理化参数（失重比，总可溶性固形物，可滴定的酸度，总抗坏血酸和颜色变化）。因此，壳聚糖膜在水果保鲜的工业应用中具有巨大的潜力。草莓的总可溶性固形物，可滴定酸度，总抗坏血酸和颜色变化最明显。因此，壳聚糖膜在水果保鲜的工业应用中具有巨大的潜力。草莓的总可溶性固形物，可滴定酸度，总抗坏血酸和颜色变化最明显。因此，壳聚糖膜在水果保鲜的工业应用中具有巨大的潜力。