啤酒花浸膏对壳聚糖/聚乙烯双层膜的性能影响及释放行为

Effect of Hops Extract on the Properties and Release Behavior of Chitosan/Polyethylene Bilayer Film

为抑制食品中有害微生物的生长繁殖,同时延缓食品品质变化、延长食品货架期,对储存食品进行适当包装尤为重要。本实验制备了含有啤酒花浸膏的壳聚糖/聚乙烯(polyethylene,PE)双层抑菌膜,研究了啤酒花浸膏添加量对抑菌膜表面结构、物理性能和抑菌活性的影响,以及在不同温度(4、25、35℃)和不同食品模拟体系(体积分数10%、50%、95%乙醇)中的释放行为。结果表明:啤酒花浸膏的加入使双层抑菌膜的耐水性增强,且对紫外光具有更高的屏障活性,同时赋予薄膜良好的抗氧化及抑菌活性,且含0.2 g/100 mL啤酒花浸膏的双层抑菌膜性能最佳。在相同条件下,啤酒花浸膏添加量越高,释放率也越高,且释放量随着温度和食品模拟液中乙醇体积分数的升高而增加,表明含啤酒花浸膏的壳聚糖/PE双层膜抑菌膜可用于高脂类食品的包装。因此,含有啤酒花浸膏的壳聚糖/PE双层抑菌膜既可弥补可食性单层膜阻水性差的不足,又能赋予聚乙烯包装膜所不具备的抑菌功能。

Proper packaging of foods is of particular importance for inhibiting the growth and reproduction of harmful microorganisms in foods during storage,delaying the quality deterioration and extending the shelf life.Chitosan-coated antimicrobial polyethylene(PE)bilayer films incorporated with hops extract were prepared in this study to investigate the effects of different concentrations of hops extract on the surface structure,physical properties and antibacterial activity of the films.Furthermore,the release behavior of hops extract from the films was investigated in simulated food systems(ethanol solutions at 10%,50%,and 95%,V/V)at different temperatures(4,25 and 35℃).The results showed that the addition of hops extract especially at 0.2 g/100 mL increased the water resistance and UV barrier capacity of the film and imparted good antioxidant and antimicrobial activity to it.Under the same conditions,the release percentage of hops extract increased with increasing its concentration,and the release amount similarly increased with increasing temperature and ethanol concentration,which indicates that the chitosan-coated antibacterial PE bilayer films could be used for the packaging of high-fat foods.Moreover,the antibacterial films not only overcome the poor water resistance of single-layer edible films,but also had antibacterial effects while PE packaging films do not have.