高负载柠檬醛抗菌复合膜的制备与性能

Preparation and Properties of Antibacterial Composite Films with HighLoading of Citral

使用抗菌包装材料是延缓水果腐烂变质的有效方法,从而可以最大限度地减少经济损失和健康危害。天然抗菌剂尤其是精油因其优异的抗菌性能,常被选为抗菌包装材料中的抗菌组分,但因其低水溶性、较差的稳定性和易挥发等因素导致所制得的材料机械性能较差且抗菌有效时间较短。因此,以壳聚糖(CS)与高相对分子质量羧甲基葡聚糖(HCMG)自组装形成的纳米颗粒为皮克林乳液(PE)的稳定剂,制备负载柠檬醛的皮克林乳液;再以CS、羧甲基葡聚糖(CMG)、聚乙烯醇(PVA)和PE为原料,通过溶剂流延法制备了复合膜。所制备的含负载柠檬醛的PE的抗菌复合膜(CS-CMG-PVA-PE1)的紫外-可见光透过率可达84%,拉伸强度达到32 MPa,断裂伸长率为130%,CO_(2)/O_(2)的透过率比为8。PE对柠檬醛起到了保护作用,不仅提高了柠檬醛在复合膜基材中的相容性,同时延长了包装材料的抗菌时间。更重要的是,复合膜共混液无细胞毒性,可以直接通过浸涂的方式在水果表面形成保护层,以提高水果的保质期,大大扩大了其易用性和使用范围。

The use of antibacterial packaging materials is an effective way to delay fruit rotting and spoilage,thereby minimizing economic losses and health hazards.Natural antibacterial agents,especially essential oils,are often selected as antibacterial components in antibacterial packaging materials,due to their excellent antibacterial properties.However,their low water solubility,poor stability,and easy volatility result in materials containing them having poor mechanical properties and short antibacterial efficacy time.Therefore,in this work,the citral loaded Pickering emulsion was prepared using chitosan and self-made carboxymethyl glucan self-assembled nanoparticles as emulsifier.Then,composite films with good transparency,excellent mechanical properties and long-term antibacterial properties for fruits packaging were prepared from chitosan(CS),carboxymethyl-glucan(CMG),poly(vinyl alcohol)(PVA),and Pickering emulsion(PE)by solvent casting strategy.Pickering emulsion has a protective effect on citral,which not only improves the compatibility of citral in composite film substrate,but also extends the antibacterial time of packaging materials.In this experiment,the transparency of the antibacterial composite film containing Pickering emulsion(CS-CMG-PVA-PE1)was 84%,the tensile strength was 32 MPa,and the elongation at break was 130%.More importantly,the composite polymer solution can be dipped directly on fruits as a coating for food storage to improve food shelf life,substantially expanding its ease of use and scope of use.