壳聚糖辐照降解产物涂膜保鲜草莓研究

A Study on the Coating Strawberry Conservation Effect of Chitosan Radiolysis Products

壳聚糖具有抑菌性与成膜性。将壳聚糖辐照降解得到的一系列不同粘均分子量产物进行涂膜草莓保鲜，研究涂膜液中壳聚糖粘均分子量、浓度、pH值、有机酸、明胶含量对草莓保鲜效果的影响；并设计四因素三水平正交试验。实验结果表明：1％（w／v）7．0×10^4Da壳聚糖、1％（v／v）醋酸、pH5、添加明胶0．5％的涂膜配方具有最好的保鲜效果；在常温（20℃、湿度80％～90％）下可以延长贮藏期2d；低温（3℃-4℃、湿度80％-90％）下可以延长贮藏期3d。

Chitosan has antimicrobial activity and film reforming properties. Using a series of different molecular weight of degraded ehitosan which products by radiolysis for strawberry preservation, studied the effect on refreshment strawberry by using Viscosity-average Molecular Weight of chitosan in the solution coating, concentration, pH, acid solvent, gelatin contentions on strawberry preservation; And designs the orthogonal test of four factors at three different levels. Test results show that when the recipe 1% viscosity average molecular weight of 7.0 × 10^4Da, the pH is 5, add 0.5 % of gelatin has the best preservation effect. Chitosan coating can increase the storage life of 2 d at room temperature （20 ℃ , HR80 % -90 % ） , and can extend the storage life of 3 d at low temperatures （3 ℃ -4 ℃ , HR80 % -90 % ） .