聚乙烯醇/纳米银薄膜的制备及其对黄骨鱼保鲜效果的研究

目的研究聚乙烯醇(PVA)/纳米银薄膜的抑菌性能,探索食品保鲜包装新方法。方法以PVA和水为基本原料,戊二醛为改性剂,用溶液流延法制备含有不同质量分数(1%,2%,3%)纳米银的PVA薄膜,分别表征其力学性能和耐水性能。将鱼肉用薄膜包裹,在4℃下贮藏,每隔3 d取样测定菌落数并进行感官分析。结果 PVA/纳米银薄膜对鱼肉有明显的抑菌作用,当纳米银添加质量分数为1%时,薄膜的拉伸强度为19.41 MPa,断裂伸长率为49%,力学性能良好;吸水率为32.2%,润湿角为55.1°,疏水性较好;与空白组相比,鱼肉货架期延长了4 d左右。结论质量分数为1%的纳米银能够增强薄膜的抑菌效果、有效维持鱼肉的感官品质,因此,在冷链运输中有很好的应用前景。

Preparation of PVA/Nano-silver Film and Its Effect on Preservation of Yellow Bone Fish

The work aims to study the antibacterial properties of PVA/nano-silver film and explore new methods for food preservation packaging. PVA film with different mass fractions of nano-silver(1%, 2%, 3%) was prepared by solution casting method, with PVA and water as the basic materials and glutaraldehyde as the modifier. The mechanical and hydrophobic properties of the film were characterized. When the fish meat was wrapped in films and stored at 4 ℃, the number of colonies was measured and the sensory analysis was performed every 3 days. PVA/nano-silver film had obvious antibacterial effect on fish. When the mass fraction of nano-silver was 1%, the tensile strength of the film was 19.41 MPa, while the elongation at break was 49%;therefore, the mechanical properties were good. The water absorption rate was 32.2%, while the wetting angle was 55.1°;therefore, the hydrophobicity was good. In the antibacterial experiment, compared with the blank group, the shelf life of the fish could be extended for about 4 days. 1%(mass fraction) nano-silver can enhance the antibacterial effect of the film and maintain the sensory quality of the fish effectively. Therefore, the film has good application prospects in cold chain transportation.