Abstract：
The present study synthesized a new type of ε-polylysine (PL) modified chitosan film (TO-CH-PL) through TEMPO (2,2,6,6-Tetramethylpiperidine) oxidation system. Firstly, the physicochemical properties of the TO-CH-PL were characterized using Fourier transform infrared spectroscopy, scanning electron microscopy, and energy dispersive spectrometer analysis. Results proved that PL was successfully grafted onto chitosan molecules. Based on the water vapor, oxygen permeability, and mechanical analysis, the TO-CH-PL film demonstrated higher physical properties than chitosan and PE films. Secondly, the TO-CH-PL film\'s preservation effect on pork fillets was evaluated. Due to the significant retardation of growth of the aerobic plate count (APC), total volatile basic nitrogen (TVBN), and thiobarbituric acid reactive substances (TBARS), as well as the changes of pH and color in packaged pork, TO-CH-PL film exhibited better preservation effects for the pork samples. According to the criteria of TVBN values (<15 mg/100 g), compared with CH and PE films, TO-CH-PL film can prolong the shelf life of pork for 2 to 3 days. Therefore, PL-modified chitosan films could be introduced as an alternative method to maintain the quality indices and extend the shelf life of pork during refrigerated storage.
摘要：
本研究通过TEMPO（2,2,6,6-四甲基哌啶）氧化体系合成了一种新型的ε-聚赖氨酸（PL）改性壳聚糖膜（TO-CH-PL）。首先,用傅里叶变换红外光谱对TO-CH-PL的理化性质进行了表征,扫描电子显微镜，和能量色散光谱仪分析。结果表明，PL成功地接枝到壳聚糖分子上。基于水蒸气，透氧性,和力学分析，TO-CH-PL膜表现出比壳聚糖和PE膜更高的物理性能。其次,评价了TO-CH-PL膜对猪肉片的保鲜效果。由于需氧平板计数（APC）的生长显着延迟，总挥发性碱性氮(TVBN)，和硫代巴比妥酸反应性物质（TBARS），以及包装猪肉的pH值和颜色的变化，TO-CH-PL膜对猪肉样品具有较好的保鲜效果。根据TVBN值的标准（<15mg/100g），与CH和PE薄膜相比，TO-CH-PL膜可以延长猪肉的保质期2～3天。因此,可以引入PL修饰的壳聚糖膜作为一种替代方法，以保持冷藏过程中猪肉的质量指标并延长其保质期。
