ε-聚赖氨酸/聚乙烯醇复合膜的抑菌活性及其对生鲜鸭肉的保鲜作用

Antibacterial of ε-poly-L-lysine/Polyvinyl Alcohol Composite Film and its Preservation Effect on Fresh Duck Meat

摘要:

本研究将ε-聚赖氨酸（ε-poly-L-lysine，ε-PL）内化于聚乙烯醇膜，获得ε-PL/聚乙烯醇复合膜，通过对其力学、抑菌圈、液体生长曲线及对包裹生鲜鸭肉后品质等实验，分析复合膜抑菌及维持生鲜鸭肉品质特性。结果表明：ε-PL浓度低于4%，50 ℃烘干5 h时，复合膜成型良好；3% ε-PL的复合膜断裂拉伸应变率和拉伸强度效果最佳；固体平板条件下，复合膜对肠球菌、大肠杆菌、枯草芽孢杆菌和金黄色葡萄球菌均有抑制作用，最大抑菌圈直径分别达到26.78 mm、26.48 mm、32.93 mm和27.83 mm；液体体系中，20 h后可完全抑制这四株菌株生长，抑菌效果随抑菌剂浓度增加而显著提升（p<0.05）；10 ℃贮藏时，与空白组相比，4% ε-PL的复合膜有效抑制了生鲜鸭肉储藏过程中TVB-N含量的升高，显著降低其菌落总数（p<0.05），延长货架期4 d以上。综合来看，ε-PL/聚乙烯醇复合膜具有良好抑菌特性，应用于生鲜鸭肉贮藏具有良好的保鲜效果。

Abstract:

In this work, ε-poly-L-lysine (ε-PL) was internalized in a polyvinyl alcohol film to obtain an ε-PL/polyvinyl alcohol composite film. Its mechanics, inhibition zone, the liquid growth curve and the quality of the packaged fresh duck meat were detected to analyze the antibacterial effect of the composite film and preservation effect of fresh duck meat. The results showed that, when the ε-PL concentration is lower than 4%, the composite film is well formed by dryingat 50 ℃ for 5 h. The tensile strain rate and tensile strength of the composite film of 3% ε-PL were the best. In Solid plate condition, the composite film had inhibitory effects on Enterococcus, Escherichia coli, Bacillus subtilis and Staphylococcus aureus, and the diameter of the largest inhibition zone were 26.78 mm, 26.48 mm, 32.93 mm and 27.83 mm, respectively. In the liquid system, after 20 h, the growth of these four strains was completely inhibited, and the antibacterial effect increased significantly with the increase of the concentration of the inhibitor (p<0.05). When storage at 10 ℃, compared with the blank group, the 4% ε-PL composite film effectively inhibited the increase of TVB-N, and reduced significantly the total number of colonies (p<0.05), resulting in extending the storage more than 4 days. Therefore, the ε-PL/polyvinyl alcohol composite film had good bacteriostatic properties and could be suitable for storage of fresh duck meat with good preservation effect.