壳聚糖-氢化咖啡酸接枝共聚物的制备及其应用

Preparation and Application of Chitosan-Hydrocaffeic Acid Grafting Copolymer

采用壳聚糖(CS)与二氢咖啡酸(HCA)在EDC交联剂催化下反应生成壳聚糖-氢化咖啡酸(CS-HCA)共聚物。通过红外光谱和自由氨基含量测试分析,结果显示,在CS改性过程中,其自由氨基含量大幅降低,与HCA的羧基发生接枝共聚反应。以蒸馏水为对照组,CS溶液以及CS-HCA共聚物溶液分别涂膜樱桃番茄后贮藏13 d,对比测定果实的失重率、腐烂率、可滴定酸含量以及Vc含量。结果表明:相对于对照组和CS涂膜,CS-HCA共聚物涂膜处理能够更有效地抑制樱桃番茄质量损失和腐烂速度,减缓可滴定酸和Vc含量的下降,对樱桃番茄具有更佳的保鲜效果。

Chitosan-hydrocaffeic acid (CS-HCA) copolymer was synthesized by the reaction of chitosan (CS) and dihydrocaffeic acid (HCA) catalyzed by EDC crosslinker.Through FTIR and free amino content analysis,the results showed that the content of free amino group decreased greatly during CS modification,and the grafting copolymerization took place with the carboxyl group of HCA.Using distilled water as control group,pure CS solution and CS-HCA copolymer solution were respectively coated with cherry tomatoes and stored for 13 days.The weight loss rate,decay rate,titratable acid content and Vc content of the fruit were determined.The results showed that:compared with control group and CS coating,CS-HCA copolymer coating could more effectively inhibit the weight loss and decay rate of cherry tomatoes,slow down the decline of titratable acid and Vc content,and had better preservation effect on cherry fruit.