ε-聚赖氨酸接枝壳聚糖的成膜特性及其对鸡肉保鲜效果

Study on Film Forming Characteristic ofε-Polylysine Grafted Chitosan and Its Preservation Effects on Chicken

本研究采用2,2,6,6-四甲基哌啶(2,2,6,6-Tetramethylpiperidine,TEMPO)氧化体系合成了一种新型ε-聚赖氨酸(PL)接枝壳聚糖膜(TO-CH-PL膜)。以壳聚糖膜(CH)和聚乙烯膜(PE)为对照,通过水蒸气透过率、氧气渗透率和机械特性测定了膜的物理特性,采用傅里叶变换红外光谱和扫描电镜对TO-CH-PL膜的理化性质进行了表征,最后考察了10℃贮存6 d过程中TO-CH-PL膜对鸡肉的保鲜效果。结果表明,PL通过氧化交联成功地接枝到壳聚糖分子上,得到的TO-CH-PL膜比其他对照组薄膜具有更高的物理性能。在保鲜效果方面,TO-CHPL膜显著延缓了鸡肉菌落总数、TVB-N和TBARS的增加,以及鸡肉的pH和颜色的变化,对鸡肉样品具有较好的保鲜效果。因此,TO-CH-PL膜有望作为冷藏过程中延长鸡肉货架期的一种替代方式。

A novelε-polylysine(PL)-modified chitosan membrane(TO-CH-PL)was synthesized by a 2,2,6,6-tetramethylpiperidine(TEMPO)oxidation system.Chitosan film(CH)and polyethylene film(PE)were used as control groups.The water vapor permeability,oxygen permeability and mechanical properties were employed to determine the physical properties of membranes.Meanwhile,the physicochemical properties of TO-CH-PL film was characterized by Fourier transform infrared spectroscopy and scanning electron microscopy.Finally,the preservation effect of TO-CH-PL film on chicken was investigated during storage at 10℃for 6 d.The results showed that PL was successfully grafted onto chitosan molecules through TEMPO oxidation system,the obtained TO-CH-PL membrane exhibited higher physical properties than other selected films.Considering the preservation effect of TO-CH-PL film,the results indicated that the increasing rate of TPC,TVB-N and TBARS,as well as the changes of pH and color of chicken could be significantly delayed by applying the TO-CH-PL membrane.It can be concluded the well preservation effect of TO-CH-PL film on chicken samples.Therefore,PL-modified chitosan films can be used as an alternative method to extend the shelf life of chicken during refrigeration.